DTC U3004:16 [START STOP UNIT]

id0902p6025200

Description

ACC relay circuit malfunction

Detection condition

•  Start stop unit detects that the ACC monitor voltage of less than 2.5 V for 1 s or more with the ignition switched to ACC or ON (engine off or on).

Fail-safe function

Not applicable

Possible cause

•  ACC relay malfunction

•  ACC relay circuit malfunction

―  Short to ground in wiring harness between MAIN 200 A fuse and ACC relay terminal C

―  IG2 30 A fuse malfunction

―  MAIN 200 A fuse malfunction

―  Open circuit in wiring harness between battery positive terminal and ACC relay terminal C

•  Start stop unit connector or terminal malfunction

•  Short to ground in wiring harness between ACC relay terminal D and start stop unit terminal 1E

•  MIRROR 7.5 A fuse malfunction

•  Open circuit in wiring harness between ACC relay terminal D and start stop unit terminal 1E

•  Start stop unit malfunction

Description	ACC relay circuit malfunction
Detection condition	• Start stop unit detects that the ACC monitor voltage of less than 2.5 V for 1 s or more with the ignition switched to ACC or ON (engine off or on).
Fail-safe function	Not applicable
Possible cause	• ACC relay malfunction • ACC relay circuit malfunction ― Short to ground in wiring harness between MAIN 200 A fuse and ACC relay terminal C ― IG2 30 A fuse malfunction ― MAIN 200 A fuse malfunction ― Open circuit in wiring harness between battery positive terminal and ACC relay terminal C • Start stop unit connector or terminal malfunction • Short to ground in wiring harness between ACC relay terminal D and start stop unit terminal 1E • MIRROR 7.5 A fuse malfunction • Open circuit in wiring harness between ACC relay terminal D and start stop unit terminal 1E • Start stop unit malfunction

Diagnostic Procedure

Step	Inspection		Action
1	INSPECT ACC RELAY • 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].) • Remove the ACC relay. (See RELAY LOCATION.) • Inspect the ACC relay. (See RELAY INSPECTION.) • Is the ACC relay normal?	Yes	Go to the next step.
1		No	Replace the ACC relay, then go to Step 6. (See RELAY LOCATION.)
2	INSPECT FOR OPEN CIRCUIT OR SHORT TO GROUND IN ACC RELAY CIRCUIT • Verify that the ACC relay is removed. • 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].) • Measure the voltage at the ACC relay terminal C (wiring harness-side). • Is the voltage B+?	Yes	Go to the next step.
2		No	Inspect the IG2 30 A and MAIN 200 A fuse. • If the fuse is blown: ― Refer to the wiring diagram and verify whether or not there is a common connector between MAIN 200 A fuse and ACC relay terminal C. 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. • Replace the fuse. • If the fuse is damaged: ― Replace the fuse. • If the fuse is normal: ― Refer to the wiring diagram and verify whether or not there is a common connector between battery positive terminal and ACC relay terminal C. 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 6.
3	INSPECT START STOP UNIT CONNECTOR CONDITION • 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 start stop 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.
3		No	Repair or replace the connector, then go to Step 6.
4	INSPECT FOR SHORT TO GROUND IN ACC RELAY CIRCUIT • Verify that the ACC relay is removed. • Verify that the start stop unit connector is disconnected. • Inspect for continuity between the following terminals (wiring harness-side) and body ground: ― ACC relay terminal D ― Start stop unit terminal 1E • Is there continuity?	Yes	Inspect the MIRROR 7.5 A fuse. • If the fuse is blown: ― Refer to the wiring diagram and verify whether or not there is a common connector between MIRROR 7.5 A fuse and start stop unit terminal 1E. 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. • Replace the fuse. • If the fuse is damaged: ― Replace the fuse. • If the fuse is normal: ― Refer to the wiring diagram and verify whether or not there is a common connector between ACC relay terminal D and MIRROR 7.5 A fuse. 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 6.
4		No	Go to the next step.
5	INSPECT FOR OPEN CIRCUIT IN ACC RELAY CIRCUIT • Verify that the ACC relay is removed. • Verify that the start stop unit connector is disconnected. • Inspect for continuity between ACC relay terminal D (wiring harness-side) and start stop unit terminal 1E (wiring harness-side). • Is there continuity?	Yes	Go to the next step.
5		No	Inspect the MIRROR 7.5 A fuse. • If the fuse is damaged: ― Replace the fuse. • If the fuse is normal: ― Refer to the wiring diagram and verify whether or not there is a common connector between ACC relay terminal D and start stop unit terminal 1E. 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 the next step.
6	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 start stop unit using the M-MDS. (See CLEARING DTC [START STOP UNIT].) • Switch the ignition to ACC or ON (engine off or on) and wait for 1 s or more. • Retrieve the start stop unit DTCs using the M-MDS. (See DTC INSPECTION [START STOP UNIT].) • Is the same DTC displayed?	Yes	Repeat the inspection from Step 1. • If the malfunction recurs, replace the start stop unit. (See START STOP UNIT REMOVAL/INSTALLATION.) Go to the next step.
6		No	Go to the next step.
7	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 [START STOP UNIT].)
7		No	DTC troubleshooting completed.