Driver side low beam headlight quit working when ignition was turned on. Headlight was working fine when the vehicle was parked. Blown light indicator on instrument cluster appeared. When changing out the light I discovered all the wires inside the headlight enclosure were damaged due to heat. All of the wires insulation was dry rotted, sections of the insulation broken off of the wires and shorted out together. I have many years of vehicle wiring troubleshooting and design. The wires in the headlights do not have the appropriate jacket rating for the headlight location where they were installed by BMW. I believe the heat from the headlights dried out and made the wire jacket brittle. After investigation of the left headlight housing both headlights require the internal harness of each headlight to be replaced due to heat and dry rot. The shorting of the wires only blew my headlight bulb and not the fuse in the system. This could be the reason for the other persons complained about their headlights turning on and off while driving. If left unchecked this could cause other problems in the cars electrical system and be dangerous if the lights shorted out during a night drive.

- Ocala, FL, USA

The contact owns a 2007 BMW Z4. The contact stated that when driving at various speeds, the headlights would flicker. The manufacturer was made aware of the failure. The vehicle was not repaired. The approximate failure mileage was 49,000.

- Tarzana, CA, USA