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ABS Warning Light Does Not Come ON at Ignition Switch ON




ABS Warning Light Does Not Come ON at Ignition Switch ON

Wiring Diagram










Circuit Description

ABS control module transmits indication ON signal of ABS warning light to combination meter in order to turn ABS warning light ON. And then, combination meter turns ABS warning light ON.

If the ABS is in good condition, ABS control module transmits indication ON signal to combination meter in order to turn ABS warning light ON at the ignition switch ON, keeps it ON for 2 seconds and then turns it OFF. If an abnormality in the system is detected, ABS warning light is turned ON continuously by ABS control module. Also, it is turned ON continuously by light driver module when ABS control module connector is disconnected.

Troubleshooting



1. Warning light check

Turn ignition switch to ON position.

Do other warning lights come ON?
YES
Substitute a known-good combination meter and recheck. If warning light remains OFF, substitute a known-good ABS hydraulic unit / control module assembly and recheck.
NO
Go to Step 2.

2. Fuse check

Is circuit fuse for combination meter in good condition?
YES
Go to Step 3.
NO
Replace fuse and check for short circuit to ground.

3. Combination meter power source circuit check

Remove combination meter with ignition switch turned OFF.
Check for proper connection to "RED/BLK" and "BLK" wires of combination meter connector.
If OK then turn ON ignition switch and measure voltage at "RED/BLK" wire of combination meter connector and vehicle body ground.

Is it 10 - 14 V?
YES
Go to Step 4.
NO
Repair power source circuit for combination meter.

4. Combination meter ground circuit check

Measure resistance between "BLK" wires of combination meter connector and vehicle body ground.

Are resistance less than 2 ohms?
YES
Substitute a known-good combination meter and recheck.
NO
"BLK" circuit open or high resistance.