Inspection Procedure 23

INSPECTION PROCEDURE 23: Radio: Preset stations are erased.

Memory Backup Power Circuit:

CIRCUIT OPERATION
Power is continuously supplied to the radio and CD player or radio and CD player with CD changer.

TECHNICAL DESCRIPTION (COMMENT)
The cause is probably a faulty radio and CD player or radio and CD player with CD changer memory backup power supply system circuit.

TROUBLESHOOTING HINTS
- Damaged wiring harness or connector.
- Malfunction of the radio and CD player or radio and CD player with CD changer. Memory Backup Power Circuit

DIAGNOSIS

Required Special Tools:
- MB991223: Harness set
- MB992006: Extra Fine Probe

STEP 1. Measure at radio and CD player or radio and CD player with CD changer connector C-117 in order to check the power supply circuit to the radio and CD player or radio and CD player with CD changer (through the battery).







1. Disconnect radio and CD player or radio and CD player with CD changer connector C-117, and measure at the wiring harness side.







2. Measure the voltage between terminal number 11 and ground.
- The voltage should measure approximately 12 volts (battery positive voltage).

Q: Is the measured voltage approximately 12 volts (battery positive voltage)?

YES : Replace the radio and CD player or radio and CD player with CD changer. Check that a memory is retained.

NO : Go to Step 2.

STEP 2. Check radio and CD player or radio and CD player with CD changer connector C-117 for loose, corroded or damaged terminals, or terminals pushed back in the connector.







Q: Is radio and CD player or radio and CD player with CD changer connector C-117 in good condition?

YES : Go to Step 3.

NO : Repair or replace the component(s). Check that a memory is retained.

STEP 3. Check the wiring harness between radio and CD player or radio and CD player with CD changer connector C-117 (terminal 11) and the battery.







NOTE: Also check intermediate connector C-24 for loose, corroded, or damaged terminals, or terminals pushed back in the connector. If intermediate connector C-24 is damaged, repair or replace the connector as described.

Q: Is the wiring harness between radio and CD player or radio and CD player with CD changer connector C-117 (terminal 11) and the battery in good condition?

YES : Repair or replace the radio and CD player or radio and CD player with CD changer. Check that a memory is retained.

NO : Repair the wiring harness. Check that a memory is retained.