SAAB WIS ONLINE

PRE-RELEASE

DTC 51 VALVE RELAY MALFUNCTION

DTC 51 VALVE RELAY MALFUNCTION

DIAGNOSIS:

Faulty valve relay

TROUBLE SYMPTOM:


ABS does not operate.

EBD does not operate.

Note

In addition to the ABS warning light, brake warning light illuminates.



WIRING DIAGRAM:


CHECK INPUT VOLTAGE OF ABSCM&H/U.

Turn the ignition switch to OFF.

Disconnect the connector from ABSCM& H/U.

Run the engine at idle.

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

Connector & terminal

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

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

Is the voltage 10 — 15 V?

Yes


No

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


CHECK GROUND CIRCUIT OF ABSCM&H/U.

Turn the ignition switch to OFF.

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

Connector & terminal

(B301) No. 15 — Chassis ground:

Is the resistance less than 0.5 Ω?

Yes


No

Repair the ABSCM&H/U ground harness.


CHECK POOR CONTACT IN CONNECTORS.

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

Yes

Repair the connector.


No


CHECK ABSCM&H/U.

Connect all connectors.

Erase the memory.

Perform the inspection mode.

Read out the DTC.

Is the same DTC as in current diagnosis still being output?

Yes

Replace the ABSCM&H/U.


No


CHECK ANY OTHER DTC APPEARANCE.

Are other DTCs being output?

Yes

Proceed with the diagnosis corresponding to DTC.


No

A temporary poor contact.


PRE-RELEASE