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NO.6 BOTH ABS WARNING LIGHT AND BRAKE SYSTEM WARNING LIGHT STAY ON MORE THAN 4 s WITH IGNITION SWITCH ON

id040300901600

6 | Both ABS warning light and BRAKE system warning light stay on more than 4 s with ignition switch on.
[TROUBLESHOOTING HINTS] • ABS (ABS/TCS) HU/CM detects ABS proportioning system malfunction. • ABS (ABS/TCS) HU/CM detects low voltage in power supply (ABS (ABS/TCS) CM ingestion terminal Z voltage is below about 9 to 10 V). • ABS (ABS/TCS) HU/CM does not operate. • Malfunction of communication network.

Diagnostic procedure

STEP | INSPECTION | ACTION
--- | --- | ---
1 | INSPECT ABS (ABS/TCS) HU/CM POWER SUPPLY FUSE Is ABS (ABS/TCS) HU/CM ignition power supply fuse normal? | Yes | Go to next step. Check for a short to ground on blown fuse's circuit.
No | Repair or replace as necessary. Install appropriate amperage fuse.
2 | INSPECT WIRING HARNESS BETWEEN ABS HU/CM AND DLC-2 FOR CONTINUITY AND SHORTS Perform DTC inspection. Is error message displayed regarding communication between ABS (ABS/TCS) HU/CM and WDS or equivalent? | Yes | If a communication error message is displayed even after inspecting according to procedure displayed on WDS or equivalent, go to step 8.
No | Go to next step.
3 | INSPECT FOR DTCS IN ABS (ABS/TCS) HU/CM Have DTCs been recorded in memory? | Yes | Perform inspection using appropriate DTC.
No | Go to next step.
4 | INSPECT PID/DATA IN ABS (ABS/TCS) HU/CM Inspect the following items using WDS or equivalent PID/DATA monitor function. • ABS_LAMP (ABS warning light) • BRAKE_ LMP (BRAKE system warning light) • ABS_VOLT (power supply voltage) Is ABS_LAMP and BRAKE_LMP ON after more than 4 s with ignition switch on? | Yes | Go to Step 7.
No | Go to next step.
5 | INSPECT ABS (ABS/TCS) HU/CM IGNITION POWER SUPPLY SYSTEM (TERMINAL Z) Inspect the voltage for PID/DATA monitor ABS_VOLT item. Specification: approx.10 V Is voltage within specification? | Yes | Replace ABS (ABS/TCS) HU/CM (open or short in ground circuit in ABS HU/CM)
No | Go to next step.
6 | INSPECT BATTERY Is battery voltage normal? | Yes | Go to next step.
No | Inspect battery and charging system.
7 | INSPECT CHARGING SYSTEM Is battery voltage normal with electrical load (A/C, headlight, etc.) on and engine idling? | Yes | Go to next step.
No | Inspect charging system (drive belt tension, generator, etc.).
*8 | INSPECT WIRING HARNESS BETWEEN ABS (ABS/TCS) HU/CM POWER SUPPLY AND ABS (ABS/TCS) HU/CM FOR CONTINUITY Disconnect ABS (ABS/TCS) HU/CM connector. Turn the ignition switch to ON. Is voltage approx. 12 V at connector terminal Z? | Yes | Go to next step.
No | Inspect for connection of ABS (ABS/TCS) HU/CM connector securely.
*9 | INSPECT WIRING HARNESS BETWEEN ABS (ABS/TCS) HU/CM GROUND FOR CONTINUITY Turn ignition switch LOOK. Is there continuity between connector terminal AC and ground? | Yes | If a malfunction error message is displayed on WDS or equivalent in Step 1 inspection, go to next step. If a malfunction error message is not displayed on WDS or equivalent in Step 1 inspection, troubleshooting is completed.
No | Repair wiring harness between ABS (ABS/TCS) HU/CM and ground.
*10 | INSPECT WIRING HARNESS BETWEEN ABS (ABS/TCS) HU/CM AND DLC-2 FOR CONTINUITY Is there continuity between connector terminal O, R and DLC-2? | Yes | Go to next step.
No | Repair wiring harness between ABS (ABS/TCS) HU/CM and DLC-2.
11 | INSPECT WIRING HARNESS BETWEEN ABS (ABS/TCS) HU/CM AND DLC-2 FOR SHORT TO BATTERY Is voltage approx. 12 V at connector terminal O, R? | Yes | Repair wiring harness between ABS (ABS/TCS) HU/CM and DLC-2.
No | Go to next step.
12 | INSPECT WIRING HARNESS BETWEEN ABS HU/CM AND DLC-2 FOR SHORT TO GROUND Is there continuity between connector terminal O, R and ground? | Yes | Repair wiring harness between ABS (ABS/TCS) HU/CM and DLC-2.
No | Replace ABS (ABS/TCS) HU/CM (communication circuit malfunction in ABS (ABS/TCS) HU/CM)