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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.
  • Disconnect the negative battery terminal before performing any work that requires handling of connectors.
DETERMINING SHORT BETWEEN CIRCUITS LOCATION (CAN-BUS No. 7) (US) DIAGNOSTIC PROCEDURE

Step Inspection Action
1 INSPECT BODY CONTROL MODULE (BCM) FOR SHORT BETWEEN CIRCUITS
Yes Go to the next step.
No Replace the body control module (BCM) because there is a short between circuits in the body control module (BCM).
(See BODY CONTROL MODULE (BCM) REMOVAL/INSTALLATION .)
2 INSPECT CAN LINE BETWEEN CONNECTOR C-49 AND BODY CONTROL MODULE (BCM) FOR SHORT BETWEEN CIRCUITS
Yes Repair or replace the wiring harness between the body control module (BCM) and connector C-49 because the wiring harness is shorted between circuits.
No Go to the next step.
3 INSPECT JB NO. 2 FOR SHORT BETWEEN CIRCUITS
Yes Replace the JB No. 2 because there is a short between circuits in the JB No. 2.
No Go to the next step.
4 INSPECT BETWEEN AUDIO AMPLIFIER AND CONNECTOR C-48 FOR SHORT BETWEEN CIRCUITS
  • Switch the ignition off.
  • Disconnect the negative battery terminal. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION (US) .)
  • Inspect for continuity between audio amplifier terminals 2N and 2M. (With Bose® type audio).
  • Inspect for continuity between audio amplifier terminals 1Q and 1S. (Without Bose® type audio)
  • Is there continuity?
Yes Go to the next step.
No Go to Step 6.
5 INSPECT AUDIO AMPLIFIER FOR SHORT BETWEEN CIRCUITS
  • Disconnect the audio amplifier connector.
  • Inspect for continuity between audio amplifier terminals 2N and 2M (wiring harness side). (With Bose® type audio).
  • Inspect for continuity between audio amplifier terminals 1Q and 1S (wiring harness side). (Without Bose® type audio)
  • Is there continuity?
Yes Repair or replace the wiring harness between the audio amplifier and connector C-48 because the wiring harness is shorted between circuits.
No Replace the audio amplifier because there is a short between circuits in the audio amplifier.
(See AUDIO AMPLIFIER REMOVAL/INSTALLATION .)
6 INSPECT BETWEEN CONNECTOR C-48 AND CONNECTOR C-13 FOR SHORT BETWEEN CIRCUITS
Yes Repair or replace the wiring harness between the connector C-48 and connector C-13 because the wiring harness is shorted between circuits.
No Go to the next step.
7 INSPECT CONNECTIVITY MASTER UNIT (CMU) FOR SHORT BETWEEN CIRCUITS
  • Switch the ignition off.
  • Disconnect the negative battery terminal. (See NEGATIVE BATTERY TERMINAL DISCONNECTION/CONNECTION (US) .)
  • Disconnect the connectivity master unit (CMU) connector.
  • Connect the connector C-13.
  • Connect the negative battery terminal. (See NEGATIVE BATTERY TERMINAL .)
  • Switch the ignition ON (engine off).
  • Measure the voltage at body control module (BCM) terminals 4R and 4Q.
  • Is the voltage at body control module (BCM) terminals 4R and 4Q the same?
Yes Repair or replace the wiring harness between the connectivity master unit (CMU) and connector C-13 because the wiring harness is shorted between circuits.
No Replace the connectivity master unit (CMU) because there is a short between circuits in the connectivity master unit (CMU).
(See CONNECTIVITY MASTER UNIT (CMU) REMOVAL/INSTALLATION .)