9CBB, 9CBF, 9CC0 E70 X5 AHL Malfunction

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Contents

Adaptive Headlamp Malfunction

Faults 9CBB, 9CBF, 9CC0

E70 X5


Complaint

There is a check control message displayed in either the control display and/or the instrument cluster informing the driver of a malfunction with the adaptive headlamps. The lighting function of the headlamps is unaffected, only the automatic movements influenced by the vehicles movements are inoperative.


Cause

Several faults are stored in the Foot Rest Module. 9CBB short circuit fault, 9CBF left stepper motor controller, no communication, 9CC0 right stepper motor controller, no communication. The faults stored are currently present and reoccur if they are cleared. There is a short that is present within the stepper motor controller circuit for either of the headlamps. The stepper motor controllers are supplied power by the same wire from the FRM. The repair for this complaint would involve checking the wiring to the individual headlamps, possibly replacing an individual stepper motor controller for a specific headlamp. If the fault has been occurring for an extended period of time, it is possible that the FRM may require replacement to remedy complaint after the vehicle has been repaired.


Correction

The most likely cause is a faulty/shorted Stepper Motor Controller. In order to isolate a particular stepper motor controller a wiring schematic is necessary to determine which pin to remove in the headlamp connector to isolate that controller. The FRM is designed to deactivate voltage to the stepper motor controllers if a short is detected. When isolating the stepper motor controllers, monitor the voltage, battery voltage should be present on the wire that supplies power to the SMC’s when no short is detected. Voltage will be deactivated after 1 min. if a short is detected in the circuit, within that first minute when a short is detected only a few volts will be present on that line. The SMC is located on the underside of the headlamp, there is a black cover 2”x 3” with 4 screws holding it in the headlamp. Once the 4 screws are removed the cover along with SMC can be removed easily. It is recommended removing the forward section of the fender liner on that particular side, to easily access backside of headlamp instead of removing the complete headlamp as some instructions describe.

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