DTC U1A4B:16 [REAR VEHICLE MONITORING SYSTEM]

id0902z2950200

DESCRIPTION

Rear vehicle monitoring control module (LH) power supply circuit malfunction
DETECTION CONDITION
•  Rear vehicle monitoring control module (LH) power supply circuit voltage is below 9 V for 1 s or more.
POSSIBLE CAUSE
•  PCM DTC is stored.
•  Battery malfunction
•  Generator malfunction
•  Rear vehicle monitoring control module (LH) connector or terminals malfunction
•  Rear vehicle monitoring control module (LH) power supply circuit malfunction
―  Short to ground in wiring harness between METER 15 A fuse and rear vehicle monitoring control module (LH) terminal F
―  METER 15 A fuse malfunction
―  Open circuit in wiring harness between ignition switch (IG1)*1/IG1 relay*2 and rear vehicle monitoring control module (LH) terminal F
•  Rear vehicle monitoring control module (LH) malfunction

*1  :Vehicles without advanced keyless entry and push button start system
*2  :Vehicles with advanced keyless entry and push button start system

Diagnostic Procedure

STEP

INSPECTION

ACTION
1
CONFIRM PCM DTC
•  Perform the PCM DTC inspection using the M-MDS.
•  Are any DTCs present?
Yes
Go to the applicable DTC inspection.
(See DTC TABLE [MZR 1.5, MZR 1.6].)
(See DTC TABLE [MZR 2.0, MZR 2.5].)
(See DTC TABLE [MZR 2.0 DISI i-stop].)
(See DTC TABLE [MZR 2.3 DISI Turbo].)
(See DTC TABLE [MZR-CD 2.2].)
(See DTC TABLE [MZ-CD 1.6].)
No
Go to the next step.
2
INSPECT BATTERY
•  Inspect the battery.
•  Is there any malfunction?
Yes
Recharge or replace the battery, then go to Step 6.
(See BATTERY RECHARGING [MZR 1.5, MZR 1.6].)
(See BATTERY RECHARGING [MZR 2.0, MZR 2.5].)
(See BATTERY RECHARGING [MZR 2.0 DISI i-stop].)
(See BATTERY RECHARGING [MZR 2.3 DISI Turbo].)
(See BATTERY RECHARGING [MZR-CD 2.2].)
(See BATTERY RECHARGING [MZ-CD 1.6].)
(See BATTERY REMOVAL/INSTALLATION [MZR 1.5, MZR 1.6].)
(See BATTERY REMOVAL/INSTALLATION [MZR 2.0, MZR 2.5].)
(See BATTERY REMOVAL/INSTALLATION [MZR 2.0 DISI i-stop].)
(See BATTERY REMOVAL/INSTALLATION [MZR 2.3 DISI Turbo].)
(See BATTERY REMOVAL/INSTALLATION [MZR-CD 2.2].)
(See BATTERY REMOVAL/INSTALLATION [MZ-CD 1.6].)
No
Go to the next step.
3
INSPECT GENERATOR
•  Inspect the generator.
•  Is there any malfunction?
Yes
Replace the generator, then go to Step 6.
(See GENERATOR REMOVAL/INSTALLATION [MZR 1.5, MZR 1.6].)
(See GENERATOR REMOVAL/INSTALLATION [MZR 2.0, MZR 2.5].)
(See GENERATOR REMOVAL/INSTALLATION [MZR 2.0 DISI i-stop].)
(See GENERATOR REMOVAL/INSTALLATION [MZR 2.3 DISI Turbo].)
(See GENERATOR REMOVAL/INSTALLATION [MZR-CD 2.2].)
(See GENERATOR REMOVAL/INSTALLATION [MZ-CD 1.6].)
No
Go to the next step.
4
INSPECT REAR VEHICLE MONITORING CONTROL MODULE (LH) CONNECTOR CONDITION
•  Switch the ignition to off.
•  Disconnect the negative battery cable.
•  Disconnect the rear vehicle monitoring control module (LH) connector.
•  Inspect the connectors and terminals (corrosion, damage, pin disconnection).
•  Is there any malfunction?
Yes
Repair or replace the connector or terminals, then go to Step 6.
No
Go to the next step.
5
INSPECT REAR VEHICLE MONITORING CONTROL MODULE (LH) POWER SUPPLY CIRCUIT FOR SHORT TO GROUND AND OPEN CIRCUIT
•  Verify that the rear vehicle monitoring control module (LH) connector is disconnected.
•  Reconnect the negative battery cable.
•  Switch the ignition to ON.
•  Measure the voltage at the rear vehicle monitoring control module (LH) terminal F (wiring harness-side).
•  Is the voltage B+?
Yes
Go to the next step.
No
Inspect the METER 15 A fuse.
•  If the fuse is blown:
―  Repair or replace the wiring harness for a possible short to ground.
―  Replace the fuse.
•  If the fuse is deterioration:
―  Replace the fuse.
•  If the fuse is normal:
―  Repair or replace the wiring harness for a possible open circuit.
Go to the next step.
6
VERIFY TROUBLESHOOTING COMPLETED
•  Make sure to reconnect all disconnected connectors.
•  Reconnect the negative battery cable.
•  Clear the DTC from rear vehicle monitoring control module using the M-MDS.
•  Switch the ignition to ON and wait for 1.5 s or more.
•  Perform the rear vehicle monitoring control module DTC inspection using the M-MDS.
•  Is the same DTC present?
Yes
Repeat the inspection from Step 1.
•  If the malfunction recurs, replace the rear vehicle monitoring control module (LH).
Go to the next step.
No
Go to the next step.
7
VERIFY THAT NO OTHER DTCs ARE PRESENT
•  Are any DTCs present?
Yes
Go to the applicable DTC inspection.
(See DTC TABLE [REAR VEHICLE MONITORING SYSTEM].)
No
DTC troubleshooting completed.