Brake System

Component Location





General Description

The ABS ECU supplies battery power to the electric motor by way of a motor relay which is controlled by the Electronic Control Unit(ECU). The electric motor pump supplies hydraulic pressure to all wheel brake calipers by operating the piston inside the pump.

DTC Description

The ABS ECU monitors the pump motor relay or fuse open, open or short in motor or motor lock and then sets this code if a malfunction is detected.

DTC Detecting Condition





Monitor Actuation Test

1. Connect scantool to Data Link Connector(DLC)
2. Ignition "ON" & Engine "OFF".
3. Select the "Actuation Test" mode on the scantool.
4. Inspect opearating status of all valves with Actuation Test.

Specification : It's normal if operating sound is heard.





5. Does the motor operate normally?
YES
> Fault is intermittent caused by poor connection in power harness (ABS1) and/or HECU's connector or was repaired and HECU memory was not cleared. Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage. Repair or replace as necessary and then go to "Verification Of Vehicle Repair" procedure.
NO
> Go to "W/Harness Inspection" procedure.

Terminal and Connector Inspection

1. Many malfunctions in the electrical system are caused by poor harness(es) and terminal conditions. Faults can also be caused by interference from other electrical systems, and mechanical or chemical damage.
2. Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage.
3. Has a problem been found?
YES
> Repair as necessary and then go to "Verification Of Vehicle Repair" procedure.
NO
> Go to "Power Circuit Inspection" procedure.

Power Circuit Inspection

1. Ignition "OFF"
2. Disconnect HECU connector.
3. Ignition "ON" & Engine "OFF".
4. Measure voltage between terminal "9(ESC : 1)" of the HECU harness connector and chassis ground.

Specification : Approx. B+





5. Is the measured voltage within specifications?
YES
> Go to "Ground Circuit Inspection" procedure.
NO
> Check for open or short in power harness between battery terminal(+) and terminal "9(ESC : 1)" of the HECU harness connector. Check for open or blown 40 A ABS2 fuse referring to "Circuit Diagram". Repair as necessary and then go to "Verification Of Vehicle Repair" procedure

Ground Circuit Inspection

1. Ignition "OFF".
2. Check for open or short in power harness between battery terminal(+) and terminal "9(ESC :1)" of the HECU harness connector. Check for open or blown 40A ABS2 fuse referring to "Circuit Diagram". Repair as necessary and then go to "Verification Of Vehicle Repair" procedure.

Specification : Approx. below 1Ohms





3. Is the measured resistance within specifications?
YES
> Go to "Component Inspection" procedure.
NO
> Check for damaged harness and poor connection between terminal "8, 24(ESC : 16, 47)" of the HECU harness connector and chassis ground. Repair as necessary and then go to "Verification Of Vehicle Repair" procedure.

Component Inspection

1. Ignition "OFF".
2. Engine "ON".
3. Start and drive vehicle in gear and maintain vehicle speed is approx. 12 km/h or more(7.5 mph or more)
4. Does warning lamp remain On?
YES
> Substitute with a known-good HECU and check for proper operation. If problem is corrected, replace HECU and then go to "Verification Of Vehicle Repair" procedure.
NO
> Fault is intermittent caused by open or short of power harness (ABS2) and/or faulty HECU or was repaired and HECU memory was not cleared. Go to the applicable troubleshooting procedure.

Verification Of Vehicle Repair

After a repair, it is essential to verify that the fault has been corrected.
1. Connect scantool and select "Diagnostic Trouble Codes(DTCs)" mode.
2. Using a scantool, Clear DTC.
3. Operate the vehicle within DTC Detecting Condition in General Information. (Start and drive vehicle in gear and maintain vehicle speed is approx. 10 km/h or more(6.2 mph or more))
4. Are any DTCs present ?
YES
> Go to the applicable troubleshooting procedure.
NO
> System performing to specification at this time.