Pinpoint Test AA: DTC U0253:00

Information and Entertainment System

Pinpoint Test AA: DTC U0253:00

Normal Operation

- DTC U0253:00 (Lost Communication With Accessory Protocol Interface Module: No Sub Type Information)- set by the Audio Front Control Module (ACM) and audio DSP (Digital Signal Processing) module when it is missing network messages from the Accessory Protocol Interface Module (APIM) over the Infotainment Controller Area Network (I-CAN) for more than 5 seconds with the ignition in the RUN position.

This pinpoint test is intended to diagnose the following:

- Communication network concern

- Audio system concern

- APIM (Accessory Protocol Interface Module)

PINPOINT TEST AA : DTC U0253:00

AA1 CHECK FOR LOST COMMUNICATION DTCs

- Ignition ON.

- Clear continuous DTCs from all modules.

- Ignition OFF.

- Ignition ON.

- Wait at least 10 seconds.

- Retrieve all continuous DTCs from all modules.

Is DTC U0253:00 set in any audio system module?

Yes
GO to AA2.

No
The system is operating correctly at this time. The DTC may have been set due to high network traffic or an intermittent fault condition.

AA2 CHECK FOR BATTERY VOLTAGE OUT-OF-RANGE DTCs

- Carry out the self-test for the following modules:
- ACM (Audio Front Control Module)

- APIM (Accessory Protocol Interface Module)

- Audio DSP (Digital Signal Processing) module (if equipped)


Is DTC U3003:16 or U3003:17 recorded in any module?

Yes
For an audio system module, REFER to DTC Charts Information and Entertainment Systems.

No
GO to AA3.

AA3 CHECK FOR DTC U0253:00 SET IN MULTIPLE MODULES

- Review the recorded results from the self-test.

Is DTC U0253:00 set in more than one module?

Yes
GO to AA4.

No
If there is an observable symptom, GO to Symptom Chart - General Audio System to diagnose the observed symptom. Symptom Chart - General Audio System

If there is no observable symptom, CHECK the I-CAN (Infotainment Controller Area Network) wiring between the APIM (Accessory Protocol Interface Module) and the module in question for an intermittent fault.

AA4 CHECK FOR CORRECT APIM (Accessory Protocol Interface Module) OPERATION

- Ignition OFF.

- Disconnect the APIM (Accessory Protocol Interface Module) connector.

- Check for:
- corrosion

- damaged pins

- pushed-out pins


- Connect the APIM (Accessory Protocol Interface Module) connector and make sure it seats correctly.

- Wait 2 minutes for the APIM (Accessory Protocol Interface Module) to re-initialize.

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

Is the concern still present?

Yes
INSTALL a new APIM (Accessory Protocol Interface Module). REFER to Accessory Protocol Interface Module (APIM) Accessory Protocol Interface Module (APIM). TEST the system for normal operation.

No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. CLEAR all continuous DTCs.