Inspection Procedure 20

Preset Station are Erased.

Memory Backup Power Circuit:

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

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

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

DIAGNOSIS

Required Special Tool:
- MB991223: Harness set

STEP 1. Check the radio, tape player, CD player and CD auto changer memory backup power supply circuit by back probing.




1. Do not disconnect radio, tape player, CD player and CD auto changer connector C-22.




2. Measure the voltage between terminal number 11 and ground by backprobing.

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

YES: Replace the radio, tape player, CD player and CD auto changer. Check that a memory is retained.

NO: Go to Step 2.




STEP 2. Check harness connector C-22 at the radio, tape player, CD player and CD auto changer for damage.

Q: Is harness connector C-22 in good condition?

YES: Go to Step 3.

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







STEP 3. Check the wiring harness between radio, tape player, CD player and CD auto changer connector C-22 (terminal 11) and battery.

NOTE: After inspecting intermediate connector C-89 and joint connector C-78, inspect the wire. If intermediate connector C-89 and joint connector C-78 are damaged, repair or replace them. Refer to Harness Connector Inspection.

Q: Are the wiring harness between the connector C-22 (terminal 11) and battery in good condition?

YES: Replace the radio, tape player, CD player and CD auto changer. Check that a memory is retained.

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