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

• 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.

• Disconnect the negative battery terminal before performing any work that requires handling of connectors.

Step	Inspection	Action
1	INSPECT CAN LINE BETWEEN BODY CONTROL MODULE (BCM) AND emergency call unit FOR SHORT TO POWER SUPPLY • 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. • Connect the negative battery terminal. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION [(E)].) • Switch the ignition ON (engine off). • Measure the voltage at body control module (BCM) terminals 3V and 3U (wiring harness side). • Is the voltage between 1.5—3.5 V?	Yes	Replace the body control module (BCM) because there is a short to the power supply in the body control module (BCM). (See BODY CONTROL MODULE (BCM) REMOVAL/INSTALLATION [(E)].)
No	Go to the next step.
2	INSPECT EMERGENCY CALL UNIT FOR SHORT TO POWER SUPPLY • Switch the ignition off. • Disconnect the negative battery terminal. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION [(E)].) • Disconnect the emergency call unit connector. • Connect the connector 3 which has body control module (BCM) terminals 3V and 3U. • Connect the negative battery terminal. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION [(E)].) • Switch the ignition ON (engine off). • Measure the voltage at body control module (BCM) terminals 3V and 3U. • Is the voltage between 1.5—3.5 V?	Yes	Replace the emergency call unit because there is a short to the power supply in the emergency call unit. (See EMERGENCY CALL UNIT REMOVAL/INSTALLATION.)
No	Repair or replace the wiring harness between the emergency call unit and body control module (BCM) because the wiring harness is shorted to the power supply.

Step

Inspection

Action

INSPECT CAN LINE BETWEEN BODY CONTROL MODULE (BCM) AND emergency call unit FOR SHORT TO POWER SUPPLY

• 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.

• Connect the negative battery terminal.

(See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION [(E)].)

• Switch the ignition ON (engine off).

• Measure the voltage at body control module (BCM) terminals 3V and 3U (wiring harness side).

• Is the voltage between 1.5—3.5 V?

Yes

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

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

Go to the next step.

INSPECT EMERGENCY CALL UNIT FOR SHORT TO POWER SUPPLY

• Switch the ignition off.

• Disconnect the negative battery terminal.

(See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION [(E)].)

• Disconnect the emergency call unit connector.

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

• Connect the negative battery terminal.

(See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION [(E)].)

• Switch the ignition ON (engine off).

• Measure the voltage at body control module (BCM) terminals 3V and 3U.

• Is the voltage between 1.5—3.5 V?

Yes

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

(See EMERGENCY CALL UNIT REMOVAL/INSTALLATION.)

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

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