DTC C0023:14 [REAR BODY CONTROL MODULE (RBCM)]

id0902p4015100

Without Smart Brake Support (SBS)

Description

Brake light circuit malfunction

Detection condition

•  Rear body control module (RBCM) detects any of the following conditions:

―  Brake lights/high-mount brake light illuminated even though driver or system does not illuminate brake lights/high-mount brake lights.

―  Brake lights/high-mount brake light not illuminated even though driver depresses brake pedal.

―  Brake lights/high-mount brake light not illuminated even though system illuminates brake lights/high-mount brake light.

Fail-safe function

Not applicable

Possible cause

•  Brake light bulb (LH) malfunction

•  Brake light bulb (RH) malfunction

•  High-mount brake light connector or terminal malfunction

•  Brake light (LH) connector or terminal malfunction

•  Brake light (RH) connector or terminal malfunction

•  Open circuit in wiring harness between the following terminals:

―  Brake light (LH) terminal A—Body ground

―  Brake light (RH) terminal A—Body ground

―  High-mount brake light terminal A—Body ground

•  Rear body control module (RBCM) connector or terminal malfunction

•  Short to ground in wiring harness between the following terminals:

―  Rear body control module (RBCM) terminal 4D—Brake light (LH) terminal C

―  Rear body control module (RBCM) terminal 4D—Brake light (RH) terminal C

―  Rear body control module (RBCM) terminal 4D—High-mount brake light terminal B

•  Short to power supply in wiring harness between the following terminals:

―  Rear body control module (RBCM) terminal 4D—Brake light (LH) terminal C

―  Rear body control module (RBCM) terminal 4D—Brake light (RH) terminal C

―  Rear body control module (RBCM) terminal 4D—High-mount brake light terminal B

•  Open circuit in wiring harness between the following terminals:

―  Rear body control module (RBCM) terminal 4D—Brake light (LH) terminal C

―  Rear body control module (RBCM) terminal 4D—Brake light (RH) terminal C

―  Rear body control module (RBCM) terminal 4D—High-mount brake light terminal B

•  High-mount brake light malfunction

•  Brake light (LH) malfunction

•  Brake light (RH) malfunction

•  Rear body control module (RBCM) malfunction

Description	Brake light circuit malfunction
Detection condition	• Rear body control module (RBCM) detects any of the following conditions: ― Brake lights/high-mount brake light illuminated even though driver or system does not illuminate brake lights/high-mount brake lights. ― Brake lights/high-mount brake light not illuminated even though driver depresses brake pedal. ― Brake lights/high-mount brake light not illuminated even though system illuminates brake lights/high-mount brake light.
Fail-safe function	Not applicable
Possible cause	• Brake light bulb (LH) malfunction • Brake light bulb (RH) malfunction • High-mount brake light connector or terminal malfunction • Brake light (LH) connector or terminal malfunction • Brake light (RH) connector or terminal malfunction • Open circuit in wiring harness between the following terminals: ― Brake light (LH) terminal A—Body ground ― Brake light (RH) terminal A—Body ground ― High-mount brake light terminal A—Body ground • Rear body control module (RBCM) connector or terminal malfunction • Short to ground in wiring harness between the following terminals: ― Rear body control module (RBCM) terminal 4D—Brake light (LH) terminal C ― Rear body control module (RBCM) terminal 4D—Brake light (RH) terminal C ― Rear body control module (RBCM) terminal 4D—High-mount brake light terminal B • Short to power supply in wiring harness between the following terminals: ― Rear body control module (RBCM) terminal 4D—Brake light (LH) terminal C ― Rear body control module (RBCM) terminal 4D—Brake light (RH) terminal C ― Rear body control module (RBCM) terminal 4D—High-mount brake light terminal B • Open circuit in wiring harness between the following terminals: ― Rear body control module (RBCM) terminal 4D—Brake light (LH) terminal C ― Rear body control module (RBCM) terminal 4D—Brake light (RH) terminal C ― Rear body control module (RBCM) terminal 4D—High-mount brake light terminal B • High-mount brake light malfunction • Brake light (LH) malfunction • Brake light (RH) malfunction • Rear body control module (RBCM) malfunction

Diagnostic Procedure

Step	Inspection		Action
1	VERIFY REAR BODY CONTROL MODULE (FBCM) DTCs AGAIN • Clear the DTC for the rear body control module (RBCM) using the M-MDS. (See CLEARING DTC [REAR BODY CONTROL MODULE (RBCM)].) • Depress the brake pedal. • Retrieve the rear body control module (RBCM) DTCs using the M-MDS. (See DTC INSPECTION [REAR BODY CONTROL MODULE (RBCM)].) • Is the same DTC displayed?	Yes	Brake light (bulb type) • Go to the next step. Brake light (LED type) • Go to Step 4.
1		No	Go to Step 18.
2	INSPECT BRAKE LIGHT BULB (LH) • Inspect the brake light bulb (LH). • Is the brake light bulb (LH) normal?	Yes	Go to the next step.
2		No	Replace the brake light bulb (LH), then go to Step 18. (See BRAKE LIGHT/TAILLIGHT BULB REMOVAL/INSTALLATION.)
3	INSPECT BRAKE LIGHT BULB (RH) • Inspect the brake light bulb (RH). • Is the brake light bulb (RH) normal?	Yes	Go to the next step.
3		No	Replace the brake light bulb (RH), then go to Step 18. (See BRAKE LIGHT/TAILLIGHT BULB REMOVAL/INSTALLATION.)
4	INSPECT HIGH-MOUNT BRAKE LIGHT CONNECTOR CONDITION • Switch the ignition off. • Disconnect the negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-G 1.5, SKYACTIV-G 2.0, SKYACTIV-G 2.5].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-D 1.5].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-D 2.2].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [MZR 1.6].) • Disconnect the high-mount brake light connector. • Inspect the connector engagement and connection condition and inspect the terminals for damage, deformation, corrosion, or disconnection. • Is the connector normal?	Yes	Go to the next step.
4		No	Repair or replace the connector, then go to Step 18.
5	INSPECT BRAKE LIGHT (LH) CONNECTOR CONDITION • Disconnect the brake light (LH) connector. • Inspect the connector engagement and connection condition and inspect the terminals for damage, deformation, corrosion, or disconnection. • Is the connector normal?	Yes	Go to the next step.
5		No	Repair or replace the connector, then go to Step 18.
6	INSPECT BRAKE LIGHT (RH) CONNECTOR CONDITION • Disconnect the brake light (RH) connector. • Inspect the connector engagement and connection condition and inspect the terminals for damage, deformation, corrosion, or disconnection. • Is the connector normal?	Yes	Go to the next step.
6		No	Repair or replace the connector, then go to Step 18.
7	INSPECT FOR OPEN CIRCUIT IN BRAKE LIGHT GROUND CIRCUIT • Verify that the high-mount brake light, brake light (LH) and brake light (RH) connectors are disconnected. • Inspect for continuity between the following terminals (wiring harness-side): ― Brake light (LH) terminal A—Body ground ― Brake light (RH) terminal A—Body ground ― High-mount brake light terminal A—Body ground • Is there continuity?	Yes	Go to the next step.
7		No	Refer to the wiring diagram and verify whether or not there is a common connector between the following terminals: • Brake light (LH) terminal A—Body ground • Brake light (RH) terminal A—Body ground • High-mount brake light terminal A—Body ground If there is a common connector: • Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for an open circuit. • Repair or replace the malfunctioning part. If there is no common connector: • Repair or replace the wiring harness which has an open circuit. Go to Step 18.
8	INSPECT REAR BODY CONTROL MODULE (RBCM) CONNECTOR CONDITION • Disconnect the rear body control module (RBCM) connector. • Inspect the connector engagement and connection condition and inspect the terminals for damage, deformation, corrosion, or disconnection. • Is the connector normal?	Yes	Go to the next step.
8		No	Repair or replace the connector, then go to Step 18.
9	INSPECT FOR SHORT TO GROUND IN BRAKE LIGHT CIRCUIT • Verify that the high-mount brake light, brake light (LH), brake light (RH) and rear body control module (RBCM) connectors are disconnected. • Inspect for continuity between rear body control module (RBCM) terminal 4D (wiring harness-side) and body ground. • Is there continuity?	Yes	Refer to the wiring diagram and verify whether or not there is a common connector between the following terminals: • Rear body control module (RBCM) terminal 4D—Brake light (LH) terminal C • Rear body control module (RBCM) terminal 4D—Brake light (RH) terminal C • Rear body control module (RBCM) terminal 4D—High-mount brake light terminal B If there is a common connector: • Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for a short to ground. • Repair or replace the malfunctioning part. If there is no common connector: • Repair or replace the wiring harness which has a short to ground. Go to Step 18.
9		No	Go to the next step.
10	INSPECT FOR SHORT TO POWER SUPPLY IN BRAKE LIGHT CIRCUIT • Verify that the high-mount brake light, brake light (LH), brake light (RH) and rear body control module (RBCM) connectors are disconnected. • Reconnect the negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-G 1.5, SKYACTIV-G 2.0, SKYACTIV-G 2.5].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-D 1.5].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-D 2.2].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [MZR 1.6].) • Switch the ignition ON (engine off or on). • Measure the voltage at the rear body control module (RBCM) terminal 4D (wiring harness-side). • Is the voltage 0 V?	Yes	Go to the next step.
10		No	Refer to the wiring diagram and verify whether or not there is a common connector between the following terminals: • Rear body control module (RBCM) terminal 4D—Brake light (LH) terminal C • Rear body control module (RBCM) terminal 4D—Brake light (RH) terminal C • Rear body control module (RBCM) terminal 4D—High-mount brake light terminal B If there is a common connector: • Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for a short to power supply. • Repair or replace the malfunctioning part. If there is no common connector: • Repair or replace the wiring harness which has a short to power supply. Go to Step 18.
11	INSPECT FOR OPEN CIRCUIT IN BRAKE LIGHT CIRCUIT • Switch the ignition off. • Disconnect the negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-G 1.5, SKYACTIV-G 2.0, SKYACTIV-G 2.5].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-D 1.5].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-D 2.2].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [MZR 1.6].) • Verify that the high-mount brake light, brake light (LH), brake light (RH) and rear body control module (RBCM) connectors are disconnected. • Inspect for continuity between the following terminals (wiring harness-side): ― Rear body control module (RBCM) terminal 4D—Brake light (LH) terminal C ― Rear body control module (RBCM) terminal 4D—Brake light (RH) terminal C ― Rear body control module (RBCM) terminal 4D—High-mount brake light terminal B • Is there continuity?	Yes	Go to the next step.
11		No	Refer to the wiring diagram and verify whether or not there is a common connector between the following terminals: • Rear body control module (RBCM) terminal 4D—Brake light (LH) terminal C • Rear body control module (RBCM) terminal 4D—Brake light (RH) terminal C • Rear body control module (RBCM) terminal 4D—High-mount brake light terminal B If there is a common connector: • Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for an open circuit. • Repair or replace the malfunctioning part. If there is no common connector: • Repair or replace the wiring harness which has an open circuit. Go to Step 18.
12	INSPECT FOR SHORT TO GROUND IN HIGH-MOUNT BRAKE LIGHT • Verify that the high-mount brake light, brake light (LH), brake light (RH) and rear body control module (RBCM) connectors are disconnected. • Reconnect the high-mount brake light connector. • Inspect for continuity between rear body control module (RBCM) terminal 4D (wiring harness-side) and body ground. • Is there continuity?	Yes	Replace the high-mount brake light, then go to Step 18. (See HIGH-MOUNT BRAKE LIGHT REMOVAL/INSTALLATION.)
12		No	Go to the next step.
13	INSPECT FOR SHORT TO POWER SUPPLY IN HIGH-MOUNT BRAKE LIGHT • Verify that the brake light (LH), brake light (RH) and rear body control module (RBCM) connectors are disconnected. • Reconnect the negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-G 1.5, SKYACTIV-G 2.0, SKYACTIV-G 2.5].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-D 1.5].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-D 2.2].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [MZR 1.6].) • Switch the ignition ON (engine off or on). • Measure the voltage at the rear body control module (RBCM) terminal 4D (wiring harness-side). • Is the voltage 0 V?	Yes	Brake light (bulb type) • Go to Step 18. Brake light (LED type) • Go to the next step.
13		No	Replace the high-mount brake light, then go to Step 18. (See HIGH-MOUNT BRAKE LIGHT REMOVAL/INSTALLATION.)
14	INSPECT FOR SHORT TO GROUND IN BRAKE LIGHT (LH) • Switch the ignition off. • Disconnect the negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-G 1.5, SKYACTIV-G 2.0, SKYACTIV-G 2.5].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-D 1.5].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-D 2.2].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [MZR 1.6].) • Verify that the brake light (LH), brake light (RH) and rear body control module (RBCM) connectors are disconnected. • Reconnect the brake light (LH) connector. • Inspect for continuity between rear body control module (RBCM) terminal 4D (wiring harness-side) and body ground. • Is there continuity?	Yes	Replace the rear combination light (LH), then go to Step 18. (See REAR COMBINATION LIGHT REMOVAL/INSTALLATION.)
14		No	Go to the next step.
15	INSPECT FOR SHORT TO POWER SUPPLY IN BRAKE LIGHT (LH) • Verify that the brake light (RH) and rear body control module (RBCM) connectors are disconnected. • Reconnect the negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-G 1.5, SKYACTIV-G 2.0, SKYACTIV-G 2.5].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-D 1.5].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-D 2.2].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [MZR 1.6].) • Switch the ignition ON (engine off or on). • Measure the voltage at the rear body control module (RBCM) terminal 4D (wiring harness-side). • Is the voltage 0 V?	Yes	Go to the next step.
15		No	Replace the rear combination light (LH), then go to Step 18. (See REAR COMBINATION LIGHT REMOVAL/INSTALLATION.)
16	INSPECT FOR SHORT TO GROUND IN BRAKE LIGHT (RH) • Switch the ignition off. • Disconnect the negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-G 1.5, SKYACTIV-G 2.0, SKYACTIV-G 2.5].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-D 1.5].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-D 2.2].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [MZR 1.6].) • Verify that the brake light (RH) and rear body control module (RBCM) connectors are disconnected. • Reconnect the brake light (RH) connector. • Inspect for continuity between rear body control module (RBCM) terminal 4D (wiring harness-side) and body ground. • Is there continuity?	Yes	Replace the rear combination light (RH), then go to Step 18. (See REAR COMBINATION LIGHT REMOVAL/INSTALLATION.)
16		No	Go to the next step.
17	INSPECT FOR SHORT TO POWER SUPPLY IN BRAKE LIGHT (RH) • Verify that the rear body control module (RBCM) connector is disconnected. • Reconnect the negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-G 1.5, SKYACTIV-G 2.0, SKYACTIV-G 2.5].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-D 1.5].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-D 2.2].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [MZR 1.6].) • Switch the ignition ON (engine off or on). • Measure the voltage at the rear body control module (RBCM) terminal 4D (wiring harness-side). • Is the voltage 0 V?	Yes	Go to the next step.
17		No	Replace the rear combination light (RH), then go to the next step. (See REAR COMBINATION LIGHT REMOVAL/INSTALLATION.)
18	VERIFY THAT REPAIRS HAVE BEEN COMPLETED • Always reconnect all disconnected connectors. • Reconnect the negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-G 1.5, SKYACTIV-G 2.0, SKYACTIV-G 2.5].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-D 1.5].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-D 2.2].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [MZR 1.6].) • Clear the DTC for the rear body control module (RBCM) using the M-MDS. (See CLEARING DTC [REAR BODY CONTROL MODULE (RBCM)].) • Depress the brake pedal. • Retrieve the rear body control module (RBCM) DTCs using the M-MDS. (See DTC INSPECTION [REAR BODY CONTROL MODULE (RBCM)].) • Is the same DTC displayed?	Yes	Repeat the inspection from Step 1. • If the malfunction recurs, replace the rear body control module (RBCM). (See REAR BODY CONTROL MODULE (RBCM) REMOVAL/INSTALLATION.) Go to the next step.
18		No	Go to the next step.
19	VERIFY IF OTHER DTCs DISPLAYED • Are any other DTCs displayed?	Yes	Repair or replace the malfunctioning part according to the applicable DTC troubleshooting. (See DTC TABLE [REAR BODY CONTROL MODULE (RBCM)].)
19		No	DTC troubleshooting completed.

With Smart Brake Support (SBS)

Description

Brake light circuit malfunction

Detection condition

•  Rear body control module (RBCM) detects any of the following conditions:

―  Brake lights/high-mount brake light illuminated even though driver or system does not illuminate brake lights/high-mount brake lights.

―  Brake lights/high-mount brake light not illuminated even though driver depresses brake pedal.

―  Brake lights/high-mount brake light not illuminated even though system illuminates brake lights/high-mount brake light.

Fail-safe function

•  Not applicable

Possible cause

•  Brake light (LH) connector or terminal malfunction

•  Brake light (RH) connector or terminal malfunction

•  Brake light unit connector or terminal malfunction

•  Open circuit in wiring harness between the following terminals:

―  Brake light (LH) terminal A—Body ground

―  Brake light (RH) terminal A—Body ground

•  Rear body control module (RBCM) connector or terminal malfunction

•  Short to ground in wiring harness between the following terminals:

―  Rear body control module (RBCM) terminal 4D—Brake light (LH) terminal C

―  Rear body control module (RBCM) terminal 4D—Brake light (RH) terminal C

―  Rear body control module (RBCM) terminal 4D—Brake light unit terminal J

•  Short to power supply in wiring harness between the following terminals:

―  Rear body control module (RBCM) terminal 4D—Brake light (LH) terminal C

―  Rear body control module (RBCM) terminal 4D—Brake light (RH) terminal C

―  Rear body control module (RBCM) terminal 4D—Brake light unit terminal J

•  Open circuit in wiring harness between the following terminals:

―  Rear body control module (RBCM) terminal 4D—Brake light (LH) terminal C

―  Rear body control module (RBCM) terminal 4D—Brake light (RH) terminal C

―  Rear body control module (RBCM) terminal 4D—Brake light unit terminal J

•  Brake light unit malfunction

•  Brake light (LH) malfunction

•  Brake light (RH) malfunction

•  Rear body control module (RBCM) malfunction

Description	Brake light circuit malfunction
Detection condition	• Rear body control module (RBCM) detects any of the following conditions: ― Brake lights/high-mount brake light illuminated even though driver or system does not illuminate brake lights/high-mount brake lights. ― Brake lights/high-mount brake light not illuminated even though driver depresses brake pedal. ― Brake lights/high-mount brake light not illuminated even though system illuminates brake lights/high-mount brake light.
Fail-safe function	• Not applicable
Possible cause	• Brake light (LH) connector or terminal malfunction • Brake light (RH) connector or terminal malfunction • Brake light unit connector or terminal malfunction • Open circuit in wiring harness between the following terminals: ― Brake light (LH) terminal A—Body ground ― Brake light (RH) terminal A—Body ground • Rear body control module (RBCM) connector or terminal malfunction • Short to ground in wiring harness between the following terminals: ― Rear body control module (RBCM) terminal 4D—Brake light (LH) terminal C ― Rear body control module (RBCM) terminal 4D—Brake light (RH) terminal C ― Rear body control module (RBCM) terminal 4D—Brake light unit terminal J • Short to power supply in wiring harness between the following terminals: ― Rear body control module (RBCM) terminal 4D—Brake light (LH) terminal C ― Rear body control module (RBCM) terminal 4D—Brake light (RH) terminal C ― Rear body control module (RBCM) terminal 4D—Brake light unit terminal J • Open circuit in wiring harness between the following terminals: ― Rear body control module (RBCM) terminal 4D—Brake light (LH) terminal C ― Rear body control module (RBCM) terminal 4D—Brake light (RH) terminal C ― Rear body control module (RBCM) terminal 4D—Brake light unit terminal J • Brake light unit malfunction • Brake light (LH) malfunction • Brake light (RH) malfunction • Rear body control module (RBCM) malfunction

Diagnostic Procedure

Step	Inspection		Action
1	VERIFY REAR BODY CONTROL MODULE (FBCM) DTCs AGAIN • Clear the DTC for the rear body control module (RBCM) using the M-MDS. (See CLEARING DTC [REAR BODY CONTROL MODULE (RBCM)].) • Depress the brake pedal. • Retrieve the rear body control module (RBCM) DTCs using the M-MDS. (See DTC INSPECTION [REAR BODY CONTROL MODULE (RBCM)].) • Is the same DTC displayed?	Yes	Brake light (bulb type) • Go to the next step. Brake light (LED type) • Go to Step 4.
1		No	Go to Step 17.
2	INSPECT BRAKE LIGHT BULB (LH) • Inspect the brake light bulb (LH). • Is the brake light bulb (LH) normal?	Yes	Go to the next step.
2		No	Replace the brake light bulb (LH), then go to Step 17. (See BRAKE LIGHT/TAILLIGHT BULB REMOVAL/INSTALLATION.)
3	INSPECT BRAKE LIGHT BULB (RH) • Inspect the brake light bulb (RH). • Is the brake light bulb (RH) normal?	Yes	Go to the next step.
3		No	Replace the brake light bulb (RH), then go to Step 17. (See BRAKE LIGHT/TAILLIGHT BULB REMOVAL/INSTALLATION.)
4	INSPECT BRAKE LIGHT UNIT CONNECTOR CONDITION • Switch the ignition off. • Disconnect the negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-G 1.5, SKYACTIV-G 2.0, SKYACTIV-G 2.5].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-D 1.5].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-D 2.2].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [MZR 1.6].) • Disconnect the brake light unit connector. • Inspect the connector engagement and connection condition and inspect the terminals for damage, deformation, corrosion, or disconnection. • Is the connector normal?	Yes	Go to the next step.
4		No	Repair or replace the connector, then go to Step 17.
5	INSPECT BRAKE LIGHT (LH) CONNECTOR CONDITION • Disconnect the brake light (LH) connector. • Inspect the connector engagement and connection condition and inspect the terminals for damage, deformation, corrosion, or disconnection. • Is the connector normal?	Yes	Go to the next step.
5		No	Repair or replace the connector, then go to Step 17.
6	INSPECT BRAKE LIGHT (RH) CONNECTOR CONDITION • Disconnect the brake light (RH) connector. • Inspect the connector engagement and connection condition and inspect the terminals for damage, deformation, corrosion, or disconnection. • Is the connector normal?	Yes	Go to the next step.
6		No	Repair or replace the connector, then go to Step 17.
7	INSPECT FOR OPEN CIRCUIT IN BRAKE LIGHT GROUND CIRCUIT • Verify that the brake light (LH) and brake light (RH) connectors are disconnected. • Inspect for continuity between the following terminals (wiring harness-side): ― Brake light (LH) terminal A—Body ground ― Brake light (RH) terminal A—Body ground • Is there continuity?	Yes	Go to the next step.
7		No	Refer to the wiring diagram and verify whether or not there is a common connector between the following terminals: • Brake light (LH) terminal A—Body ground • Brake light (RH) terminal A—Body ground If there is a common connector: • Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for an open circuit. • Repair or replace the malfunctioning part. If there is no common connector: • Repair or replace the wiring harness which has an open circuit. Go to Step 17.
8	INSPECT REAR BODY CONTROL MODULE (RBCM) CONNECTOR CONDITION • Disconnect the rear body control module (RBCM) connector. • Inspect the connector engagement and connection condition and inspect the terminals for damage, deformation, corrosion, or disconnection. • Is the connector normal?	Yes	Go to the next step.
8		No	Repair or replace the connector, then go to Step 17.
9	INSPECT FOR SHORT TO GROUND IN BRAKE LIGHT CIRCUIT • Verify that the brake light unit, brake light (LH), brake light (RH) and rear body control module (RBCM) connectors are disconnected. • Inspect for continuity between rear body control module (RBCM) terminal 4D (wiring harness-side) and body ground. • Is there continuity?	Yes	Refer to the wiring diagram and verify whether or not there is a common connector between the following terminals: • Rear body control module (RBCM) terminal 4D—Brake light (LH) terminal C • Rear body control module (RBCM) terminal 4D—Brake light (RH) terminal C • Rear body control module (RBCM) terminal 4D—Brake light unit terminal J If there is a common connector: • Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for a short to ground. • Repair or replace the malfunctioning part. If there is no common connector: • Repair or replace the wiring harness which has a short to ground. Go to Step 17.
9		No	Go to the next step.
10	INSPECT FOR SHORT TO POWER SUPPLY IN BRAKE LIGHT CIRCUIT • Verify that the brake light unit, brake light (LH), brake light (RH) and rear body control module (RBCM) connectors are disconnected. • Reconnect the negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-G 1.5, SKYACTIV-G 2.0, SKYACTIV-G 2.5].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-D 1.5].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-D 2.2].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [MZR 1.6].) • Switch the ignition ON (engine off or on). • Measure the voltage at the rear body control module (RBCM) terminal 4D (wiring harness-side). • Is the voltage 0 V?	Yes	Go to the next step.
10		No	Refer to the wiring diagram and verify whether or not there is a common connector between the following terminals: • Rear body control module (RBCM) terminal 4D—Brake light (LH) terminal C • Rear body control module (RBCM) terminal 4D—Brake light (RH) terminal C • Rear body control module (RBCM) terminal 4D—Brake light unit terminal J If there is a common connector: • Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for a short to power supply. • Repair or replace the malfunctioning part. If there is no common connector: • Repair or replace the wiring harness which has a short to power supply. Go to Step 17.
11	INSPECT FOR OPEN CIRCUIT IN BRAKE LIGHT CIRCUIT • Switch the ignition off. • Disconnect the negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-G 1.5, SKYACTIV-G 2.0, SKYACTIV-G 2.5].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-D 1.5].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-D 2.2].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [MZR 1.6].) • Verify that the brake light unit, brake light (LH), brake light (RH) and rear body control module (RBCM) connectors are disconnected. • Inspect for continuity between the following terminals (wiring harness-side): ― Rear body control module (RBCM) terminal 4D—Brake light (LH) terminal C ― Rear body control module (RBCM) terminal 4D—Brake light (RH) terminal C ― Rear body control module (RBCM) terminal 4D—Brake light unit terminal J • Is there continuity?	Yes	Go to the next step.
11		No	Refer to the wiring diagram and verify whether or not there is a common connector between the following terminals: • Rear body control module (RBCM) terminal 4D—Brake light (LH) terminal C • Rear body control module (RBCM) terminal 4D—Brake light (RH) terminal C • Rear body control module (RBCM) terminal 4D—Brake light unit terminal J If there is a common connector: • Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for an open circuit. • Repair or replace the malfunctioning part. If there is no common connector: • Repair or replace the wiring harness which has an open circuit. Go to Step 17.
12	INSPECT BRAKE LIGHT UNIT • Inspect the brake light unit. (See BRAKE LIGHT UNIT INSPECTION.) • Is the brake light unit normal?	Yes	Brake light (bulb type) • Go to Step 17. Brake light (LED type) • Go to the next step.
12		No	Replace the brake light unit, then go to Step 17. (See BRAKE LIGHT UNIT REMOVAL/INSTALLATION.)
13	INSPECT FOR SHORT TO GROUND IN BRAKE LIGHT (LH) • Verify that the brake light (LH), brake light (RH), brake light unit and rear body control module (RBCM) connectors are disconnected. • Reconnect the brake light (LH) connector. • Inspect for continuity between rear body control module (RBCM) terminal 4D (wiring harness-side) and body ground. • Is there continuity?	Yes	Replace the rear combination light (LH), then go to Step 17. (See REAR COMBINATION LIGHT REMOVAL/INSTALLATION.)
13		No	Go to the next step.
14	INSPECT FOR SHORT TO POWER SUPPLY IN BRAKE LIGHT (LH) • Verify that the brake light (RH), brake light unit and rear body control module (RBCM) connectors are disconnected. • Reconnect the negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-G 1.5, SKYACTIV-G 2.0, SKYACTIV-G 2.5].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-D 1.5].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-D 2.2].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [MZR 1.6].) • Switch the ignition ON (engine off or on). • Measure the voltage at the rear body control module (RBCM) terminal 4D (wiring harness-side). • Is the voltage 0 V?	Yes	Go to the next step.
14		No	Replace the rear combination light (LH), then go to Step 17. (See REAR COMBINATION LIGHT REMOVAL/INSTALLATION.)
15	INSPECT FOR SHORT TO GROUND IN BRAKE LIGHT (RH) • Switch the ignition off. • Disconnect the negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-G 1.5, SKYACTIV-G 2.0, SKYACTIV-G 2.5].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-D 1.5].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-D 2.2].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [MZR 1.6].) • Verify that the brake light (RH), brake light unit and rear body control module (RBCM) connectors are disconnected. • Reconnect the brake light (RH) connector. • Inspect for continuity between rear body control module (RBCM) terminal 4D (wiring harness-side) and body ground. • Is there continuity?	Yes	Replace the rear combination light (RH), then go to Step 17. (See REAR COMBINATION LIGHT REMOVAL/INSTALLATION.)
15		No	Go to the next step.
16	INSPECT FOR SHORT TO POWER SUPPLY IN BRAKE LIGHT (RH) • Verify that the brake light unit and rear body control module (RBCM) connector is disconnected. • Reconnect the negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-G 1.5, SKYACTIV-G 2.0, SKYACTIV-G 2.5].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-D 1.5].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-D 2.2].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [MZR 1.6].) • Switch the ignition ON (engine off or on). • Measure the voltage at the rear body control module (RBCM) terminal 4D (wiring harness-side). • Is the voltage 0 V?	Yes	Go to the next step.
16		No	Replace the rear combination light (RH), then go to the next step. (See REAR COMBINATION LIGHT REMOVAL/INSTALLATION.)
17	VERIFY THAT REPAIRS HAVE BEEN COMPLETED • Always reconnect all disconnected connectors. • Reconnect the negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-G 1.5, SKYACTIV-G 2.0, SKYACTIV-G 2.5].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-D 1.5].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [SKYACTIV-D 2.2].) (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION [MZR 1.6].) • Clear the DTC for the rear body control module (RBCM) using the M-MDS. (See CLEARING DTC [REAR BODY CONTROL MODULE (RBCM)].) • Depress the brake pedal. • Retrieve the rear body control module (RBCM) DTCs using the M-MDS. (See DTC INSPECTION [REAR BODY CONTROL MODULE (RBCM)].) • Is the same DTC displayed?	Yes	Repeat the inspection from Step 1. • If the malfunction recurs, replace the rear body control module (RBCM). (See REAR BODY CONTROL MODULE (RBCM) REMOVAL/INSTALLATION.) Go to the next step.
17		No	Go to the next step.
18	VERIFY IF OTHER DTCs DISPLAYED • Are any other DTCs displayed?	Yes	Repair or replace the malfunctioning part according to the applicable DTC troubleshooting. (See DTC TABLE [REAR BODY CONTROL MODULE (RBCM)].)
18		No	DTC troubleshooting completed.