Pinpoint Test AE: DTC U0155

Adaptive Headlighting

Pinpoint Tests

Pinpoint Test AE: DTC U0155

Normal Operation

The Smart Junction Box (SJB) communicates the headlamps on status to the Instrument Cluster (IC) over the Medium Speed Controller Area Network (MS-CAN). The IC acts as a gateway module and relays the information through the High Speed Controller Area Network (HS-CAN). The Headlamp Control Module (HCM) receives headlamps on status information from the IC gateway.

- DTC U0155 (Lost Communication With Instrument Panel Cluster (IC) Control Module) - an on-demand DTC that sets when the HCM does not receive communication from the IC.

This pinpoint test is intended to diagnose the following:

- HCM
- IC



PINPOINT TEST AE: DTC U0155

-------------------------------------------------
AE1 REPEAT THE HCM SELF-TEST


- Ignition ON.
- Enter the following diagnostic mode on the scan tool: HCM Self-Test.
- Clear the DTCs and repeat the HCM self-test.
- Is DTC U0155 retrieved again?

Yes
GO to AE2.

No
The vehicle is operating correctly at this time. The HCM may have temporarily lost communication with the IC.

-------------------------------------------------
AE2 CHECK OTHER MODULES FOR DTC U0155


- Enter the following diagnostic mode on the scan tool: ABS Module Self-Test.
- Carry out the self-test for other modules on the HS-CAN. The PCM, ABS module and Restraints Control Module (RCM), for example, communicate on the HS-CAN.
- Is DTC U0155 retrieved from any other module?

Yes
REFER to Information Bus.

No
GO to AE3.

-------------------------------------------------
AE3 CHECK FOR CORRECT HCM OPERATION


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

Yes
INSTALL a new HCM. REFER to Headlamp Control Module (HCM) Service and Repair. 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.

-------------------------------------------------