19 - Inspection Procedure

Preset Station are Erased.

Memory Backup Power Supply Circuit:

CIRCUIT OPERATION
The power is constantly supplied to the radio, CD player and CD auto changer.

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

TROUBLESHOOTING HINTS
- Damaged harness wire or connector.
- Malfunction of the radio, CD player and CD auto changer.

DIAGNOSIS

Required Special Tool:
- MB991223: Harness set




STEP 1. Check the radio, CD player and CD auto changer memory backup power supply circuit by back probing.
1. Do not disconnect radio, CD player and CD auto changer connector C-31.
2. Measure the voltage between terminal number 11 and ground by backprobing.

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

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

NO: Go to Step 2.




STEP 2. Check harness connector C-31 at the radio, CD player and CD auto changer for damage.

Q: Is harness connector C-31 in good condition?

YES: Go to Step 3.

NO: Repair or replace it. Refer to Harness Connector Inspection. Check that a memory is retained.







STEP 3. Check the harness wires between radio, CD player connector C-31 and battery.

Q: Are the harness wires between the connector C-31 and battery in good condition?

YES: Repair them. Check that a memory is retained.

NO: Repair or replace the radio, CD player. Check that a memory is retained.