ABS (DIAGNOSTICS) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)

DTC 51 VALVE RELAY MALFUNCTION

DTC DETECTING CONDITION:

Defective valve relay

TROUBLE SYMPTOM:

• ABS does not operate.

• EBD does not operate depending on the trouble contents.

NOTE:

Brake warning light comes on as well as ABS warning light when EBD does not operate.

WIRING DIAGRAM:

STEPCHECKYESNO

1.CHECK INPUT VOLTAGE OF ABSCM&H/U.

1) Turn the ignition switch to OFF.

2) Disconnect the ABSCM&H/U connectors.

3) Run the engine at idle.

4) Measure the voltage between ABSCM&H/U connector and chassis ground.

Connector & terminal

LHD model

(B301) No. 18 (+) — Chassis ground (−):

(B301) No. 14 (+) — Chassis ground (−):

RHD model

(F49) No. 18 (+) — Chassis ground (−):

(F49) No. 14 (+) — Chassis ground (−):

Is the voltage 10 — 15 V?

Repair the harness connector between battery and ABSCM&H/U.

2.CHECK THE ABSCM&H/U GROUND CIRCUIT.

1) Turn the ignition switch to OFF.

2) Measure the resistance between the ABSCM&H/U connector and chassis ground.

Connector & terminal

LHD model

(B301) No. 15 — Chassis ground:

RHD model

(F49) No. 15 — Chassis ground:

Is the resistance less than 0.5 Ω?

Repair the ABSCM&H/U ground harness.

3.CHECK VALVE RELAY IN ABSCM&H/U.

Measure the resistance between the ABSCM&H/U terminals.

Terminals

No. 14 — No. 15:

Is the resistance more than 1 MΩ?

Replace the ABSCM only.

4.CHECK POOR CONTACT IN CONNECTOR.

Is there poor contact in connector between generator, battery and ABSCM&H/U?

Repair the connector.

5.CHECK ABSCM&H/U.

1) Connect all connectors.

2) Erase the memory.

3) Perform the Inspection Mode.

4) Read the DTC.

Is the same DTC displayed?

Replace the ABSCM only.

6.CHECK ANY OTHER DTC ON DISPLAY.

Is there any other DTC displayed?

Check DTC using “List of Diagnostic Trouble Code (DTC)”.

Temporary poor contact occurs.