Inspection Procedure 2: No Sound is Heard. <Vehicles with audio amplifier: Long wheelbase>


caution Before replacing the radio and CD changer or audio amplifier, ensure that the power supply circuit, the earth circuit and the communication circuit are normal.












COMMENTS ON TROUBLE SYMPTOM



PROBABLE CAUSES



  • Malfunctions of radio and CD changer
  • Malfunction of audio amplifier
  • Option coding information inconsistency
  • Damaged harness wires and connectors

DIAGNOSIS PROCEDURE

STEP 1. Connector check: E-37 audio amplifier connector

Q. Is the check result normal?
Go to Step 2.
Repair the defective connector.

STEP 2. Resistance measurement at E-37 audio amplifier connector
(1)Disconnect the connector, and measure at the wiring harness side.
(2)Measure the resistance between E-37 audio amplifier connector terminal No.24 and the body earth.
OK: Continuity exists (2 Ω or less)
(3)Measure the resistance between E-37 audio amplifier connector terminal No.31 and the body earth.
OK: Continuity exists (2 Ω or less)
(4)Measure the resistance between E-37 audio amplifier connector terminal No.32 and the body earth.
OK: Continuity exists (2 Ω or less)

Q. Is the check result normal?
Go to Step 4.
Go to Step 3.

STEP 3. Check the harness wire between the E-37 audio amplifier connector terminal No.24, 31, 32 and the body earth

  • Check the earth wires for open circuit.

Q. Is the check result normal?
Check the trouble symptom.
Repair the wiring harness.

STEP 4. Voltage measurement at E-37 audio amplifier connector
(1)Disconnect the connector, and measure at the wiring harness-side connector.
(2)Voltage between E-37 audio amplifier connector terminal No.25 and the body earth
OK: Battery voltage
(3)Voltage between E-37 audio amplifier connector terminal No.35 and the body earth
OK: Battery voltage
(4)Voltage between E-37 audio amplifier connector terminal No.36 and the body earth
OK: Battery voltage

Q. Is the check result normal?
Go to Step 6.
Go to Step 5.

STEP 5. Check the harness wire between E-37 audio amplifier connector terminal No.25, 35, 36 and fusible link No.29.

  • Check the power supply lines for open circuit and short circuit.

Q. Is the check result normal?
Go to Step 10.
Repair the wiring harness.

STEP 6. Connector check: D-211 radio and CD changer connector

Q. Is the check result normal?
Go to Step 7.
Repair the defective connector.

STEP 7. Check the harness wire between D-211 radio and CD changer connector terminal No.7 and E-37 audio amplifier connector No.34.

  • Check the communication line for open circuit and short circuit.
note Prior to the wiring harness inspection, check intermediate connector D-237, and repair if necessary.

Q. Is the check result normal?
Go to Step 8.
Repair the wiring harness.

STEP 8. Connector check: E-38 audio amplifier connector

Q. Is the check result normal?
Go to Step 9.
Repair the defective connector.

STEP 9. Check the harness wire between D-211 radio and CD changer connector terminal No.17 and E-38 audio amplifier connector No.3

  • Check the communication line for open circuit and short circuit.
note Prior to the wiring harness inspection, check intermediate connector D-237, and repair if necessary.

Q. Is the check result normal?
Go to Step 10.
Repair the wiring harness.

STEP 10. Retest the system
Replace the audio amplifier, then check that the audio sound is output.

Q. Is the check result normal?
The trouble can be an intermittent malfunction (Refer to GROUP 00 - How to use Troubleshooting/inspection Service Points - How to Cope with Intermittent Malfunction ).
Replace the radio and CD changer.