DTC B1238:16 [CONNECTIVITY MASTER UNIT]

id0902n7104900


Without i-stop System

Description

Tuner and amp unit (TAU) low power supply voltage input
Detection condition
•  Connectivity master unit (CMU) detects power supply circuit voltage for tuner and amp unit (TAU) of less than 10 V for 10 s or more with the ignition switched ON (engine off or on).
Fail-safe function
Not applicable
Possible cause
•  DTCs are stored in the PCM.
•  Battery malfunction
•  Generator malfunction
•  Tuner and amp unit (TAU) connector or terminal malfunction
•  Tuner and amp unit (TAU) power supply circuit malfunction
―  Short to ground in wiring harness between MAIN 200 A fuse and tuner and amp unit (TAU) terminal 2B
―  AUDIO1 15 A fuse malfunction
―  CABIN+B 50 A fuse malfunction
―  MAIN 200 A fuse malfunction
―  Open circuit in wiring harness between battery positive terminal and tuner and amp unit (TAU) terminal 2B
•  Tuner and amp unit (TAU) malfunction

Diagnostic Procedure

Step

Inspection

Action
1
VERIFY PCM DTCs
•  Perform the DTC inspection for the PCM using the M-MDS.
•  Is a DTC displayed?
Yes
Repair the malfunctioning location according to the applicable DTC troubleshooting.
(See DTC TABLE [SKYACTIV-G 1.5, SKYACTIV-G 2.0, SKYACTIV-G 2.5].)
(See DTC TABLE [MZR 1.6].)
No
Go to the next step.
2
INSPECT BATTERY
•  Inspect the battery.
•  Is the battery normal?
Yes
Go to the next step.
No
Recharge or replace the battery, then go to Step 6.
(See BATTERY RECHARGING [SKYACTIV-G 1.5, SKYACTIV-G 2.0, SKYACTIV-G 2.5].)
(See BATTERY RECHARGING [MZR 1.6].)
(See BATTERY REMOVAL/INSTALLATION [SKYACTIV-G 1.5, SKYACTIV-G 2.0, SKYACTIV-G 2.5].)
(See BATTERY REMOVAL/INSTALLATION [MZR 1.6].)
3
INSPECT GENERATOR
•  Inspect the generator.
•  Is the generator normal?
Yes
Go to the next step.
No
Replace the generator, then go to Step 6.
(See GENERATOR REMOVAL/INSTALLATION [SKYACTIV-G 1.5, SKYACTIV-G 2.0, SKYACTIV-G 2.5 (WITHOUT i-ELOOP)].)
(See GENERATOR REMOVAL/INSTALLATION [MZR 1.6].)
4
INSPECT TUNER AND AMP UNIT (TAU) CONNECTOR CONDITION
•  Switch the ignition off.
•  Disconnect the negative battery cable.
•  Disconnect the tuner and amp unit (TAU) 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.
No
Repair or replace the connector, then go to Step 6.
5
VERIFY TUNER AND AMP UNIT (TAU) POWER SUPPLY VOLTAGE
•  Verify that the tuner and amp unit (TAU) connector is disconnected.
•  Reconnect the negative battery cable.
•  Switch the ignition ON (engine off or on).
•  Measure the voltage at tuner and amp unit (TAU) terminal 2B (wiring harness-side).
•  Is the voltage 10 V or more?
Yes
Go to the next step.
No
Inspect the AUDIO1 15 A fuse, CABIN+B 50A fuse and MAIN 200 A fuse.
•  If the fuse is blown:
―  Refer to the wiring diagram and verify if there is a common connector between MAIN 200 A fuse and tuner and amp unit (TAU) terminal 2B.
If there is a common connector:
•  Inspect the common connector and terminals for corrosion, damage, or disconnection and the common wiring harnesses for short to ground to determine the malfunctioning location.
•  Repair or replace the malfunctioning location.
If there is no common connector:
•  Repair or replace the wiring harness which is shorted 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 if there is a common connector between battery positive terminal and the tuner and amp unit (TAU) terminal 2B.
If there is a common connector:
•  Inspect the common connector and terminals for corrosion, damage, or disconnection and the common wiring harnesses for an open circuit to determine the malfunctioning location.
•  Repair or replace the malfunctioning location.
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.
•  Clear the DTC for the connectivity master unit (CMU) using the M-MDS.
•  Switch the ignition ON (engine off or on) and wait for 17 s or more.
•  Perform the DTC inspection for the connectivity master unit (CMU) using the M-MDS.
•  Is the same DTC displayed?
Yes
Repeat the inspection from Step 1.
•  If the malfunction recurs, replace the tuner and amp unit (TAU).
Go to the next step.
No
Go to the next step.
7
VERIFY IF OTHER DTCs DISPLAYED
•  Are any other DTCs displayed?
Yes
Repair the malfunctioning location according to the applicable DTC troubleshooting.
(See DTC TABLE [CONNECTIVITY MASTER UNIT].)
No
DTC troubleshooting completed.


With i-stop, without i-ELOOP

Description

Tuner and amp unit (TAU) low power supply voltage input
Detection condition
•  Connectivity master unit (CMU) detects power supply circuit voltage for tuner and amp unit (TAU) of less than 10 V for 10 s or more with the ignition switched ON (engine off or on).
Fail-safe function
Not applicable
Possible cause
•  DTCs are stored in the PCM.
•  Battery malfunction
•  Generator malfunction
•  Tuner and amp unit (TAU) connector or terminal malfunction
•  Tuner and amp unit (TAU) power supply circuit malfunction
―  Short to ground in wiring harness between AUDIO1 15 A fuse and tuner and amp unit (TAU) terminal 2B
―  AUDIO1 15 A fuse malfunction
―  Open circuit in wiring harness between DC-DC converter terminal K and tuner and amp unit (TAU) terminal 2B
•  DC-DC converter connector or terminal malfunction
•  DC-DC converter malfunction
•  Tuner and amp unit (TAU) malfunction

Diagnostic Procedure

Step

Inspection

Action
1
VERIFY PCM DTCs
•  Perform the DTC inspection for the PCM using the M-MDS.
•  Is a DTC displayed?
Yes
Repair the malfunctioning location according to the applicable DTC troubleshooting.
(See DTC TABLE [SKYACTIV-G 1.5, SKYACTIV-G 2.0, SKYACTIV-G 2.5].)
(See DTC TABLE [SKYACTIV-D 1.5].)
(See DTC TABLE [SKYACTIV-D 2.2].)
No
Go to the next step.
2
INSPECT BATTERY
•  Inspect the battery.
•  Is the battery normal?
Yes
Go to the next step.
No
Recharge or replace the battery, then go to Step 8.
(See BATTERY RECHARGING [SKYACTIV-G 1.5, SKYACTIV-G 2.0, SKYACTIV-G 2.5].)
(See BATTERY RECHARGING [SKYACTIV-D 1.5].)
(See BATTERY RECHARGING [SKYACTIV-D 2.2].)
(See BATTERY REMOVAL/INSTALLATION [SKYACTIV-G 1.5, SKYACTIV-G 2.0, SKYACTIV-G 2.5].)
(See BATTERY REMOVAL/INSTALLATION [SKYACTIV-D 1.5].)
(See BATTERY REMOVAL/INSTALLATION [SKYACTIV-D 2.2].)
3
INSPECT GENERATOR
•  Inspect the generator.
•  Is the generator normal?
Yes
Go to the next step.
No
Replace the generator, then go to Step 8.
(See GENERATOR REMOVAL/INSTALLATION [SKYACTIV-G 1.5, SKYACTIV-G 2.0, SKYACTIV-G 2.5 (WITHOUT i-ELOOP)].)
(See GENERATOR REMOVAL/INSTALLATION [SKYACTIV-D 1.5].)
(See GENERATOR REMOVAL/INSTALLATION [SKYACTIV-D 2.2 (WITHOUT i-ELOOP)].)
4
INSPECT TUNER AND AMP UNIT (TAU) CONNECTOR CONDITION
•  Switch the ignition off.
•  Disconnect the negative battery cable.
•  Disconnect the tuner and amp unit (TAU) 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.
No
Repair or replace the connector, then go to Step 8.
5
VERIFY TUNER AND AMP UNIT (TAU) POWER SUPPLY VOLTAGE
•  Verify that the tuner and amp unit (TAU) connector is disconnected.
•  Reconnect the negative battery cable.
•  Switch the ignition ON (engine off or on).
•  Measure the voltage at tuner and amp unit (TAU) terminal 2B (wiring harness-side).
•  Is the voltage 10 V or more?
Yes
Go to the next step.
No
Inspect the AUDIO1 15 A fuse.
•  If the fuse is blown:
―  Refer to the wiring diagram and verify if there is a common connector between AUDIO1 15 A fuse and tuner and amp unit (TAU) terminal 2B.
If there is a common connector:
•  Inspect the common connector and terminals for corrosion, damage, or disconnection and the common wiring harnesses for short to ground to determine the malfunctioning location.
•  Repair or replace the malfunctioning location.
If there is no common connector:
•  Repair or replace the wiring harness which is shorted 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 if there is a common connector between DC-DC converter terminal K and the tuner and amp unit (TAU) terminal 2B.
If there is a common connector:
•  Inspect the common connector and terminals for corrosion, damage, or disconnection and the common wiring harnesses for an open circuit to determine the malfunctioning location.
•  Repair or replace the malfunctioning location.
If there is no common connector:
•  Repair or replace the wiring harness which has an open circuit.
Go to Step 8.
6
INSPECT DC-DC CONVERTER CONNECTOR CONDITION
•  Switch the ignition off.
•  Disconnect the negative battery cable.
•  Disconnect the DC-DC converter 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.
No
Repair or replace the connector, then go to Step 8.
7
INSPECT DC-DC CONVERTER
•  Inspect DC-DC converter.
•  Is the DC-DC converter normal?
Yes
Go to the next step.
No
Replace the DC-DC converter, then go to the next step.
(See DC-DC CONVERTER REMOVAL/INSTALLATION [SKYACTIV-G 1.5, SKYACTIV-G 2.0, SKYACTIV-G 2.5 (WITHOUT i-ELOOP)].)
(See DC-DC CONVERTER REMOVAL/INSTALLATION [SKYACTIV-D 1.5].)
(See DC-DC CONVERTER REMOVAL/INSTALLATION [SKYACTIV-D 2.2 (WITHOUT i-ELOOP)].)
8
VERIFY THAT REPAIRS HAVE BEEN COMPLETED
•  Always reconnect all disconnected connectors.
•  Reconnect the negative battery cable.
•  Clear the DTC for the connectivity master unit (CMU) using the M-MDS.
•  Switch the ignition ON (engine off or on) and wait for 17 s or more.
•  Perform the DTC inspection for the connectivity master unit (CMU) using the M-MDS.
•  Is the same DTC displayed?
Yes
Repeat the inspection from Step 1.
•  If the malfunction recurs, replace the tuner and amp unit (TAU).
Go to the next step.
No
Go to the next step.
9
VERIFY IF OTHER DTCs DISPLAYED
•  Are any other DTCs displayed?
Yes
Repair the malfunctioning location according to the applicable DTC troubleshooting.
(See DTC TABLE [CONNECTIVITY MASTER UNIT].)
No
DTC troubleshooting completed.


With i-stop and i-ELOOP

Description

Tuner and amp unit (TAU) low power supply voltage input
Detection condition
•  Connectivity master unit (CMU) detects power supply circuit voltage for tuner and amp unit (TAU) of less than 10 V for 10 s or more with the ignition switched ON (engine off or on).
Fail-safe function
Not applicable
Possible cause
•  DTCs are stored in the PCM.
•  Battery malfunction
•  Generator malfunction
•  Tuner and amp unit (TAU) connector or terminal malfunction
•  Tuner and amp unit (TAU) power supply circuit malfunction
―  Short to ground in wiring harness between AUDIO1 15 A fuse and tuner and amp unit (TAU) terminal 2B
―  AUDIO1 15 A fuse malfunction
―  Open circuit in wiring harness between DC-DC converter (i-ELOOP) terminal 2A and tuner and amp unit (TAU) terminal 2B
•  DC-DC converter (i-ELOOP) connector or terminal malfunction
•  DC-DC converter (i-ELOOP) malfunction
•  Tuner and amp unit (TAU) malfunction

Diagnostic Procedure

Step

Inspection

Action
1
VERIFY PCM DTCs
•  Perform the DTC inspection for the PCM using the M-MDS.
•  Is a DTC displayed?
Yes
Repair the malfunctioning location according to the applicable DTC troubleshooting.
(See DTC TABLE [SKYACTIV-G 1.5, SKYACTIV-G 2.0, SKYACTIV-G 2.5].)
(See DTC TABLE [SKYACTIV-D 2.2].)
No
Go to the next step.
2
INSPECT BATTERY
•  Inspect the battery.
•  Is the battery normal?
Yes
Go to the next step.
No
Recharge or replace the battery, then go to Step 8.
(See BATTERY RECHARGING [SKYACTIV-G 1.5, SKYACTIV-G 2.0, SKYACTIV-G 2.5].)
(See BATTERY RECHARGING [SKYACTIV-D 2.2].)
(See BATTERY REMOVAL/INSTALLATION [SKYACTIV-G 1.5, SKYACTIV-G 2.0, SKYACTIV-G 2.5].)
(See BATTERY REMOVAL/INSTALLATION [SKYACTIV-D 2.2].)
3
INSPECT GENERATOR
•  Inspect the generator.
•  Is the generator normal?
Yes
Go to the next step.
No
Replace the generator, then go to Step 8.
(See GENERATOR REMOVAL/INSTALLATION [SKYACTIV-G 1.5, SKYACTIV-G 2.0, SKYACTIV-G 2.5 (WITH i-ELOOP)].)
(See GENERATOR REMOVAL/INSTALLATION [SKYACTIV-D 2.2 (WITH i-ELOOP)].)
4
INSPECT TUNER AND AMP UNIT (TAU) CONNECTOR CONDITION
•  Switch the ignition off.
•  Disconnect the negative battery cable.
•  Disconnect the tuner and amp unit (TAU) 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.
No
Repair or replace the connector, then go to Step 8.
5
VERIFY TUNER AND AMP UNIT (TAU) POWER SUPPLY VOLTAGE
•  Verify that the tuner and amp unit (TAU) connector is disconnected.
•  Reconnect the negative battery cable.
•  Switch the ignition ON (engine off or on).
•  Measure the voltage at tuner and amp unit (TAU) terminal 2B (wiring harness-side).
•  Is the voltage 10 V or more?
Yes
Go to the next step.
No
Inspect the AUDIO1 15 A fuse.
•  If the fuse is blown:
―  Refer to the wiring diagram and verify if there is a common connector between AUDIO1 15 A fuse and tuner and amp unit (TAU) terminal 2B.
If there is a common connector:
•  Inspect the common connector and terminals for corrosion, damage, or disconnection and the common wiring harnesses for short to ground to determine the malfunctioning location.
•  Repair or replace the malfunctioning location.
If there is no common connector:
•  Repair or replace the wiring harness which is shorted 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 if there is a common connector between DC-DC converter (i-ELOOP) terminal 2A and the tuner and amp unit (TAU) terminal 2B.
If there is a common connector:
•  Inspect the common connector and terminals for corrosion, damage, or disconnection and the common wiring harnesses for an open circuit to determine the malfunctioning location.
•  Repair or replace the malfunctioning location.
If there is no common connector:
•  Repair or replace the wiring harness which has an open circuit.
Go to Step 8.
6
INSPECT DC-DC CONVERTER (i-ELOOP) CONNECTOR CONDITION
•  Switch the ignition off.
•  Disconnect the negative battery cable.
•  Disconnect the service plug.
•  Disconnect the DC-DC converter (i-ELOOP) 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.
No
Repair or replace the connector, then go to Step 8.
7
INSPECT DC-DC CONVERTER (i-ELOOP)
•  Inspect DC-DC converter (i-ELOOP).
•  Is the DC-DC converter (i-ELOOP) normal?
Yes
Go to the next step.
No
Replace the DC-DC converter (i-ELOOP), then go to the next step.
(See DC-DC CONVERTER (i-ELOOP) REMOVAL/INSTALLATION [i-ELOOP].)
8
VERIFY THAT REPAIRS HAVE BEEN COMPLETED
•  Always reconnect all disconnected connectors.
•  Reconnect the service plug.
•  Reconnect the negative battery cable.
•  Clear the DTC for the connectivity master unit (CMU) using the M-MDS.
•  Switch the ignition ON (engine off or on) and wait for 17 s or more.
•  Perform the DTC inspection for the connectivity master unit (CMU) using the M-MDS.
•  Is the same DTC displayed?
Yes
Repeat the inspection from Step 1.
•  If the malfunction recurs, replace the tuner and amp unit (TAU).
Go to the next step.
No
Go to the next step.
9
VERIFY IF OTHER DTCs DISPLAYED
•  Are any other DTCs displayed?
Yes
Repair the malfunctioning location according to the applicable DTC troubleshooting.
(See DTC TABLE [CONNECTIVITY MASTER UNIT].)
No
DTC troubleshooting completed.