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Pinpoint Test AA: DTC U0140 Or DTC U0140:00




Information and Entertainment System

Pinpoint Tests

Pinpoint Test AA: DTC U0140 Or DTC U0140:00

Normal Operation

Several audio system modules receive network messages from the Smart Junction Box (SJB) via the Medium Speed Controller Area Network (MS-CAN). The following information is included in the messages:

- Ignition switch position
- Illumination dimmer control
- Accessory delay status

As more than one module receives each of these messages, all modules receiving a particular message should exhibit a symptom if the message is missing.

- DTC U0140 (Lost Communication With Body Control Module (GEM)) - set by the non-navigation Audio Control Module (ACM), the Front Controls Interface Module (FCIM) (vehicles without navigation), and the Front Display Interface Module (FDIM) when network messages are missing from the SJB for greater than 5 seconds with the ignition in RUN.
- DTC U0140:00 (Lost Communication With Body Control Module: No Sub Type Information) - set by the navigation ACM or the Accessory Protocol Interface Module (APIM) (V2 only) when network messages are missing from the SJB for greater than 5 seconds with the ignition in RUN.

This pinpoint test is intended to diagnose the following:

- Communication network concern
- Audio system concern
- SJB



PINPOINT TEST AA: DTC U0140 OR DTC U0140:00

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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 U0140 or DTC U0140:00 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.

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AA2 CHECK FOR BATTERY VOLTAGE OUT-OF-RANGE DTCs


- Carry out the self-test for the following modules:
- ACM
- APIM
- FCIM
- FDIM
- SJB
- Is DTC B1317, B1318, U3003:16 or U3003:17 recorded in any module?

Yes
For an audio system module, REFER to DTC Charts. [1][2]Diagnostic Trouble Code Descriptions

For the SJB, REFER to Body Control Systems.

No
GO to AA3.

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AA3 CHECK FOR DTC U0140 OR DTC U0140:00 SET IN MULTIPLE MODULES


- Review the recorded results from the self-test.
- Is DTC U0140 or DTC U0140:00 set in more than one audio system 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, DISREGARD the DTC.

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AA4 CHECK FOR CORRECT SJB OPERATION


- Ignition OFF.
- Disconnect the SJB connector.
- Check for:
- corrosion
- damaged pins
- pushed-out pins
- Connect the SJB connector and make sure it seats correctly.
- Operate the system and determine if the concern is still present.
- Is the concern still present?

Yes
INSTALL a new SJB. CLEAR all continuous DTCs. REPEAT the self-test.

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. REPEAT the self-test.

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