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For 1990-2009 cars only

HID Headlamps Flutter Vertically Over Bumps - keywords bump discharge down high intensity lamp light lighting loose shake up

Subject:HID Headlamps Flutter Vertically Over Bumps

Models:2008-2009 Cadillac XLR & XLR-V



The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.

Condition/Concern:

Some customers may comment when driving in the dark, the head lamp beam flutters vertically when driven on moderate to rough road surfaces. The adaptive forward lighting assembly with in the head lamp assembly allows some motion when the lamp experiences road impacts transmitted through the vehicle suspension and structure.

Recommendation/Instructions:

Inspect the lamp assembly to ensure it is properly fastened to the vehicle sub structure. Visually inspect the HID lamp assembly inside the head lamp assembly. It should be centered in the lamp opening. If no obvious issues are noted the lamp is most likely operating as intended. As with any moving part some deflection can be expected when the assembly experiences road shock inputs. Verify this is a normal condition by comparing to a like vehicle. Once verified, do not replace the headlamp assembly.

Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.