Low Tire Pressure Warning Light Does Not Come ON at Ignition Switch ON

Low Tire Pressure Warning Light Does Not Come ON at Ignition Switch ON

Wiring Diagram










Circuit Description

Operation (ON/OFF) of low tire pressure warning light is controlled by BCM. If tire pressure monitoring system is in good condition, BCM turns low tire pressure warning light ON at ignition switch ON, keeps it ON for 2 seconds and then turns it OFF. If tire pressure is lower than specified value or ID code of tire pressure sensor is not registered in BCM, low tire pressure warning light is turned ON continuously by BCM. Also, when any abnormality of system is detected, BCM makes low tire pressure warning lights up after blinks for 75 seconds. When CAN communication between BCM and combination meter fails, however, it is combination meter that makes low tire pressure warning lights up after blinks for 75 seconds.

Troubleshooting

1. Combination meter power and ground circuit check

Turn ignition switch to ON position.

Do other warning light come ON?
YES -
Go to Step 2.
NO -
Check main fuse, circuit fuse, combination meter power and ground circuit.

2. BCM power and ground circuit check

Check BCM power and ground circuit for condition referring to BCM Power Circuit and Ground Circuit Check BCM Power Circuit and Ground Circuit Check.

Is it in good condition?
YES -
Go to Step 3.
NO -
Repair circuit.

3. CAN communication circuit check

Disconnect connectors from BCM and combination meter.
Check CAN communication circuit between BCM and combination meter for open, short and high resistance.

Is each CAN communication circuit in good condition?
YES -
Go to Step 4.
NO -
Repair circuit.

4. Low tire pressure warning light operation check

Connect connector to combination meter.
Turn ignition switch to ON position.

Does low tire pressure warning lights up after blinks for 75 seconds?
YES -
Substitute a known-good BCM and recheck.
NO -
Substitute a known-good combination meter and recheck.