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Pinpoint Test AF: DTC U0126:87




Adaptive Headlighting

Pinpoint Test AF: DTC U0126:87

- DTC U0126:87 (Lost Communication With Steering Wheel Angle Sensor Module: Missing Message)- sets continuous in the Headlamp Control Module (HCM) if data messages received from the Power Steering Control Module (PSCM) over the High Speed Controller Area Network (HS-CAN) are missing. For a complete list of all network messages, refer to Information Bus.

The PSCM (Power Steering Control Module) is integrated into the steering gear.

This pinpoint test is intended to diagnose the following:

- HCM (Headlamp Control Module)

- PSCM (Power Steering Control Module)

PINPOINT TEST AF : U0126:87

NOTE: If new modules were installed prior to the DTC being set, the module configuration may be incorrectly set during the Programmable Module Installation (PMI) or the PMI (Programmable Module Installation) may not have been carried out.

AF1 VERIFY THE CUSTOMER CONCERN

- Ignition ON.

- Verify that there is an observable symptom present.

Is an observable symptom present?

Yes
GO to AF2.

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

AF2 CHECK THE COMMUNICATION NETWORK

- Enter the following diagnostic mode on the scan tool: Network Test.

- Carry out the network test.

Does the PSCM (Power Steering Control Module) pass the network test?

Yes
GO to AF3.

No
REFER to Information Bus.

AF3 RETRIEVE THE RECORDED DTCs FROM THE HCM (Headlamp Control Module) SELF-TEST

- Check for recorded DTCs from the HCM (Headlamp Control Module) self-test.

Is DTC U3003:16 or DTC U3003:17 recorded?

Yes
For DTC U3003:16, GO to Pinpoint Test AH. Pinpoint Test AH: DTC U3003:16

For DTC U3003:17 GO to Pinpoint Test AI. Pinpoint Test AI: DTC U3003:17

No
GO to AF4.

AF4 RECHECK THE HCM (Headlamp Control Module) DTCs

- Enter the following diagnostic mode on the scan tool: HCM (Headlamp Control Module) Self-Test.

- Clear the DTCs. Repeat the HCM (Headlamp Control Module) self-test.

Is DTC U0126:87 still present?

Yes
INSTALL a new steering gear. CLEAR the DTCs. REPEAT the self-test.

If DTC U0126:87 is still present, INSTALL a new HCM (Headlamp Control Module). REFER to Headlamp Control Module (HCM) . TEST the system for normal operation.

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.