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DETERMINING SHORT TO GROUND LOCATION (CAN-BUS No.8) [(E)]

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Caution

• Perform the following malfunction diagnosis only when it is diagnosed with a short to ground by CONTROLLER AREA NETWORK (CAN) MALFUNCTION DIAGNOSIS FLOW.

(See CONTROLLER AREA NETWORK (CAN) MALFUNCTION DIAGNOSIS FLOW [(E)].)

System Wiring Diagram

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Determination Procedure

Caution

• When disconnecting the connector, verify that there is no looseness, damage, deformation, corrosion, or poor connection of the connector terminals.

• When inspecting the connector, touch it with a paper clip or similar thin pin without directly inserting a tester probe into the terminal.

Step

Inspection

Action

1

INSPECT CAN LINE IN BODY CONTROL MODULE (BCM) FOR SHORT TO GROUND

•  Switch the ignition off.

•  Disconnect the negative battery terminal.
(See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION [(E)])

•  Disconnect the connector 3 which has body control module (BCM) terminals 3V and 3U.

•  Inspect for continuity at the following terminals:

―  Between body control module (BCM) terminal 3V (wiring harness side) and body ground

―  Between body control module (BCM) terminal 3U (wiring harness side) and body ground

•  Is there continuity?

Yes

Go to the next step.

No

Replace the body control module (BCM) because there is a short to ground in the body control module (BCM).

(See BODY CONTROL MODULE (BCM) REMOVAL/INSTALLATION [(E)].)

2

INSPECT CAN LINE IN EMERGENCY CALL UNIT FOR SHORT TO GROUND

•  Disconnect the emergency call unit connector.

•  Inspect for continuity at the following terminals:

―  Between emergency call unit terminal 1Q (wiring harness side) and body ground

―  Between emergency call unit terminal 1S (wiring harness side) and body ground

•  Is there continuity?

Yes

Repair or replace the wiring harness between the body control module (BCM) and emergency call unit because the wiring harness is shorted to ground.

No

Replace the emergency call unit because there is a short to ground in the emergency call unit.

(See EMERGENCY CALL UNIT REMOVAL/INSTALLATION.)

Step	Inspection		Action
1	INSPECT CAN LINE IN BODY CONTROL MODULE (BCM) FOR SHORT TO GROUND • Switch the ignition off. • Disconnect the negative battery terminal. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION [(E)]) • Disconnect the connector 3 which has body control module (BCM) terminals 3V and 3U. • Inspect for continuity at the following terminals: ― Between body control module (BCM) terminal 3V (wiring harness side) and body ground ― Between body control module (BCM) terminal 3U (wiring harness side) and body ground • Is there continuity?	Yes	Go to the next step.
1		No	Replace the body control module (BCM) because there is a short to ground in the body control module (BCM). (See BODY CONTROL MODULE (BCM) REMOVAL/INSTALLATION [(E)].)
2	INSPECT CAN LINE IN EMERGENCY CALL UNIT FOR SHORT TO GROUND • Disconnect the emergency call unit connector. • Inspect for continuity at the following terminals: ― Between emergency call unit terminal 1Q (wiring harness side) and body ground ― Between emergency call unit terminal 1S (wiring harness side) and body ground • Is there continuity?	Yes	Repair or replace the wiring harness between the body control module (BCM) and emergency call unit because the wiring harness is shorted to ground.
2		No	Replace the emergency call unit because there is a short to ground in the emergency call unit. (See EMERGENCY CALL UNIT REMOVAL/INSTALLATION.)