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Diagnostic Procedure

DTC B1238-01; SPEAKER CIRCUIT MALFUNCTION - DIAGNOSTIC PROCEDURE

Step Inspection Action
1 INSPECT AUDIO AMPLIFIER CONNECTOR CONDITION
  • Switch the ignition off.
  • Disconnect the negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION .)
  • Disconnect the audio amplifier connector.
  • Inspect the connector engagement and connection condition and inspect the terminals for damage, deformation, corrosion, or disconnection.
  • Is the connector normal?
Yes Go to the next step.
No Repair or replace the connector, then go to Step 6.
2 INSPECT TUNER AND AMP UNIT (TAU) CONNECTOR CONDITION
  • Disconnect the tuner and amp unit (TAU) connector.
  • Inspect the connector engagement and connection condition and inspect the terminals for damage, deformation, corrosion, or disconnection.
  • Is the connector normal?
Yes Go to the next step.
No Repair or replace the connector, then go to Step 6.
3 INSPECT AUDIO AMPLIFIER CIRCUIT FOR SHORT TO GROUND
  • Verify that the audio amplifier and tuner and amp unit (TAU) connectors are disconnected.
  • Inspect for continuity between the following terminals (wiring harness-side) and body ground.
    • Audio amplifier terminal 1F
    • Audio amplifier terminal 1E
    • Audio amplifier terminal 1G
    • Audio amplifier terminal 1H
    • Audio amplifier terminal 2F
    • Audio amplifier terminal 1J
    • Audio amplifier terminal 2J
    • Audio amplifier terminal 1I
    • Audio amplifier terminal 1K
      • Audio amplifier terminal 1L
  • Is there continuity?
Yes Refer to the wiring diagram and verify if there is a common connector between the following terminals.
  • Tuner and amp unit (TAU) terminal 2A and audio amplifier terminal 1F
  • Tuner and amp unit (TAU) terminal 2C and audio amplifier terminal 1E
  • Tuner and amp unit (TAU) terminal 2D and audio amplifier terminal 1G
  • Tuner and amp unit (TAU) terminal 2F and audio amplifier terminal 1H
  • Tuner and amp unit (TAU) terminal 2J and audio amplifier terminal 2F
  • Tuner and amp unit (TAU) terminal 2S and audio amplifier terminal 1J
  • Tuner and amp unit (TAU) terminal 2T and audio amplifier terminal 2J
  • Tuner and amp unit (TAU) terminal 2U and audio amplifier terminal 1I
  • Tuner and amp unit (TAU) terminal 2V and audio amplifier terminal 1K
  • Tuner and amp unit (TAU) terminal 2X and audio amplifier terminal 1L

If there is a common connector:
  • Inspect the common connector and terminals for corrosion, damage, or disconnection and the common wiring harnesses for short to ground to determine the malfunctioning location.
  • Repair or replace the malfunctioning location.

    If there is no common connector:

  • Repair or replace the wiring harness which is shorted to ground.

Go to Step 6.
No Go to the next step.
4 INSPECT AUDIO AMPLIFIER CIRCUIT FOR SHORT TO POWER SUPPLY
  • Verify that the audio amplifier and tuner and amp unit (TAU) connectors are disconnected.
  • Reconnect the negative battery cable. (See NEGATIVE BATTERY CABLE DISCONNECTION/CONNECTION .)
  • Switch the ignition ON (engine off or on).
  • Measure the voltage at the following terminals (wiring harness-side).
    • Audio amplifier terminal 1F
    • Audio amplifier terminal 1E
    • Audio amplifier terminal 1G
    • Audio amplifier terminal 1H
    • Audio amplifier terminal 2F
    • Audio amplifier terminal 1J
    • Audio amplifier terminal 2J
    • Audio amplifier terminal 1I
    • Audio amplifier terminal 1K
      • Audio amplifier terminal 1L
  • Is the voltage 0 V?
Yes Go to the next step.
No Refer to the wiring diagram and verify if there is a common connector between the following terminals.
  • Tuner and amp unit (TAU) terminal 2A and audio amplifier terminal 1F
  • Tuner and amp unit (TAU) terminal 2C and audio amplifier terminal 1E
  • Tuner and amp unit (TAU) terminal 2D and audio amplifier terminal 1G
  • Tuner and amp unit (TAU) terminal 2F and audio amplifier terminal 1H
  • Tuner and amp unit (TAU) terminal 2J and audio amplifier terminal 2F
  • Tuner and amp unit (TAU) terminal 2S and audio amplifier terminal 1J
  • Tuner and amp unit (TAU) terminal 2T and audio amplifier terminal 2J
  • Tuner and amp unit (TAU) terminal 2U and audio amplifier terminal 1I
  • Tuner and amp unit (TAU) terminal 2V and audio amplifier terminal 1K
  • Tuner and amp unit (TAU) terminal 2X and audio amplifier terminal 1L

If there is a common connector:
  • Inspect the common connector and terminals for corrosion, damage, or disconnection and the common wiring harnesses for short to power supply to determine the malfunctioning location.
  • Repair or replace the malfunctioning location.

    If there is no common connector:

  • Repair or replace the wiring harness which is shorted to the power supply.

Go to Step 6.
5 PERFORM DTC INSPECTION AND VERIFY IF MALFUNCTIONING PART IS AUDIO AMPLIFIER Yes Replace the audio amplifier, then go to the next step.
(See AUDIO AMPLIFIER REMOVAL/INSTALLATION .)
No Go to Step 7.
6 VERIFY THAT REPAIRS HAVE BEEN COMPLETED Yes Repeat the inspection from Step 1.
Go to the next step.
No Go to the next step.
7 VERIFY IF OTHER DTCs DISPLAYED
  • Are any other DTCs displayed?
Yes Repair the malfunctioning location according to the applicable DTC troubleshooting.
(See DTC TABLE [CONNECTIVITY MASTER UNIT] .)
No DTC troubleshooting completed.