DTC U1A4B:17 [REAR VEHICLE MONITORING SYSTEM]

id0902z2888500

System malfunction location

Rear vehicle monitoring control module (LH) high power supply voltage input

Detection condition

•  Power supply circuit voltage of 16 V or more is detected in rear vehicle monitoring control module (LH) for 1 s or more.

Fail-safe

•  Inhibits the rear vehicle monitoring system.

Possible cause

•  DTCs are stored in the PCM.

•  Battery malfunction

•  Generator malfunction

•  Rear vehicle monitoring control module (LH) malfunction

System wiring diagram

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System malfunction location	Rear vehicle monitoring control module (LH) high power supply voltage input
Detection condition	• Power supply circuit voltage of 16 V or more is detected in rear vehicle monitoring control module (LH) for 1 s or more.
Fail-safe	• Inhibits the rear vehicle monitoring system.
Possible cause	• DTCs are stored in the PCM. • Battery malfunction • Generator malfunction • Rear vehicle monitoring control module (LH) malfunction
System wiring diagram	—

Diagnostic Procedure

Step	Inspection		Action
1	VERIFY PCM DTCs • Perform the DTC inspection for the PCM using the M-MDS. (See ON-BOARD DIAGNOSTIC TEST [SKYACTIV-G 2.0, SKYACTIV-G 2.5].) (See ON-BOARD DIAGNOSTIC TEST [SKYACTIV-D 2.2].) • Is the DTC displayed?	Yes	Repair the malfunctioning part according to the applicable DTC troubleshooting. (See DTC TABLE [SKYACTIV-G 2.0, SKYACTIV-G 2.5].) (See DTC TABLE [SKYACTIV-D 2.2].)
1		No	Go to the next step.
2	INSPECT BATTERY • Inspect the battery. (See BATTERY INSPECTION [SKYACTIV-G 2.0, SKYACTIV-G 2.5 (WITHOUT i-stop)].) (See BATTERY INSPECTION [SKYACTIV-G 2.0, SKYACTIV-G 2.5].) (See BATTERY INSPECTION [SKYACTIV-D 2.2].) • Is the battery normal?	Yes	Go to the next step.
2		No	Replace the battery, then go to Step 4. (See BATTERY REMOVAL/INSTALLATION [SKYACTIV-G 2.0, SKYACTIV-G 2.5].) (See BATTERY REMOVAL/INSTALLATION [SKYACTIV-D 2.2].)
3	INSPECT GENERATOR • Inspect the generator. (See GENERATOR INSPECTION [SKYACTIV-G 2.0, SKYACTIV-G 2.5].) (See GENERATOR INSPECTION [SKYACTIV-D 2.2].) • Is the generator normal?	Yes	Go to the next step.
3		No	Replace the generator, then go to the next step. (See GENERATOR REMOVAL/INSTALLATION [SKYACTIV-G 2.0, SKYACTIV-G 2.5].) (See GENERATOR REMOVAL/INSTALLATION [SKYACTIV-D 2.2].)
4	VERIFY THAT REPAIRS HAVE BEEN COMPLETED • Clear the DTC for the rear vehicle monitoring control module using the M-MDS. (See CLEARING DTC [REAR VEHICLE MONITORING SYSTEM].) • Switch the ignition ON (engine off or on) and wait for 1.5 s or more. • Perform the DTC inspection for the rear vehicle monitoring control module using the M-MDS. (See DTC INSPECTION [REAR VEHICLE MONITORING SYSTEM].) • Is DTC U1A4B:17 displayed?	Yes	Repeat the inspection from Step 1. • If the malfunction recurs, replace the rear vehicle monitoring control module (LH), then go to the next step. (See REAR VEHICLE MONITORING CONTROL MODULE REMOVAL/INSTALLATION.)
4		No	Go to the next step.
5	VERIFY IF OTHER DTCs DISPLAYED • Are any other DTCs displayed?	Yes	Repair the malfunctioning part according to the applicable DTC troubleshooting. (See DTC TABLE [REAR VEHICLE MONITORING SYSTEM].)
5		No	DTC troubleshooting completed.