U0257

Diagnostic Routine L

Diagnostic Overview

U0257:00

Normal Operation and Fault Conditions

DTC Fault Trigger Conditions






Pinpoint Test

1. VERIFY THE CUSTOMER CONCERN

1. Ignition ON.

2. Verify there is an observable symptom present.

Is an observable symptom present?








2. CHECK FOR LOST COMMUNICATION DTCs (Diagnostic Trouble Codes)

1. Ignition ON.

2. Using a scan tool, clear continuous memory DTCs (Diagnostic Trouble Codes) from all modules.

3. Ignition OFF.

4. Ignition ON.

5. Wait at least 10 seconds.

6. Retrieve all continuous memory DTCs (Diagnostic Trouble Codes) from all modules.

Is DTC (Diagnostic Trouble Code) U0257:00 set in any audio system module?








3. CHECK THE AUDIO SYSTEM MODULES FOR BATTERY VOLTAGE OUT-OF-RANGE DTCs (Diagnostic Trouble Codes)

1. Using a scan tool, perform the self-test for:

- ACM (Audio Control Module)
- FCDIM (Front Control/Display Interface Module)
- APIM (Accessory Protocol Interface Module) (with SYNC(R))

Are any low or high voltage DTCs (Diagnostic Trouble Codes) recorded in any module?








4. CHECK FOR DTC (Diagnostic Trouble Code) U0257:00 SET IN MULTIPLE MODULES

1. Review the recorded results from the self-test.

Is DTC (Diagnostic Trouble Code) U0257:00 set in more than one audio system module?








5. CHECK FOR CORRECT FCDIM (Front Control/Display Interface Module) OPERATION

1. Ignition OFF.

2. Disconnect and inspect the FCDIM (Front Control/Display Interface Module) connector.

3. Repair:

- corrosion (install new connectors or terminals - clean module pins)
- damaged or bent pins - install new terminals pins
- pushed-out pins - install new pins as necessary

4. Reconnect the FCDIM (Front Control/Display Interface Module) connector. Make sure it seats and latches correctly.

5. Operate the system and determine if the concern is still present.

Is the concern still present?