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DTC 56 OPEN OR SHORT CIRCUIT IN G SENSOR CIRCUIT

DTC 56 OPEN OR SHORT CIRCUIT IN G SENSOR CIRCUIT

DIAGNOSIS:

Faulty G sensor output voltage

TROUBLE SYMPTOM:

ABS does not operate.

WIRING DIAGRAM:


CHECK OUTPUT OF G SENSOR USING Vehicle Diagnostic Interface.

Select “Current data display & Save” on the Vehicle Diagnostic Interface.

Read the G sensor output in Vehicle Diagnostic Interface data display.

Is the G sensor output on monitor display −1.25 — 1.25 m/s when G sensor is in horizontal position?

Yes


No


CHECK POOR CONTACT IN CONNECTORS.

Is there poor contact in connector between ABSCM&H/U and G sensor?

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 the 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.


CHECK INPUT VOLTAGE OF G SENSOR.

Turn the ignition switch to OFF.

Remove the console box.

Remove the G sensor from vehicle. (Do not disconnect connector.)

Turn the ignition switch to ON.

Measure the voltage between G sensor connector terminals.

Connector & terminal

(B292) No. 1 (+) — No. 3 (−):

Is the voltage 4.75 — 5.25 V?

Yes


No

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


CHECK OPEN CIRCUIT IN G SENSOR OUTPUT HARNESS AND GROUND HARNESS.

Turn the ignition switch to OFF.

Disconnect the connector from ABSCM& H/U.

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

Connector & terminal

(B301) No. 10 — No. 21:

Is the resistance 5.0 — 5.6 kΩ?

Yes


No

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


CHECK GROUND SHORT IN G SENSOR OUTPUT HARNESS.

Disconnect the connector from G sensor.

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

Connector & terminal

(B301) No. 21 — Chassis ground:

Is the resistance more than 1 MΩ?

Yes


No

Repair the harness between G sensor and ABSCM&H/U.


CHECK G SENSOR.

Connect the connector to G sensor.

Connect the connector to ABSCM&H/U.

Turn the ignition switch to ON.

Measure the voltage between G sensor connector terminals.

Connector & terminal

(B292) No. 2 (+) — No. 3 (−):

Is the voltage 2.1 — 2.5 V when G sensor is in horizontal position?

Yes


No

Replace the G sensor.


CHECK G SENSOR.

Measure the voltage between G sensor connector terminals.

Connector & terminal

(B292) No. 2 (+) — No. 3 (−):

Is the voltage 3.7 — 4.1 V when G sensor is inclined forwards to 90°?

Yes


No

Replace the G sensor.


CHECK G SENSOR.

Measure the voltage between G sensor connector terminals.

Connector & terminal

(B292) No. 2 (+) — No. 3 (−):

Is the voltage 0.5 — 0.9 V when G sensor is inclined backwards to 90°?

Yes


No

Replace the G sensor.


CHECK POOR CONTACT IN CONNECTORS.

Turn the ignition switch to OFF.

Is there poor contact in connector between ABSCM&H/U and G sensor?

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.