BMW E65 xenon headlight not working on one side
Why does the E65's xenon light not work on one side only?
Besides the bulb, the fault can be in the ballast, the bulb's ignition control unit. If a new bulb doesn't help, move the ballast to the other side: if the fault moves with it, the ballast is faulty.
How do you replace the E65's xenon bulb?
1. Twist the ballast off the sealed unit and pull it out. 2. Release the bulb's two retaining springs and replace the bulb. 3. Lock the ballast back in place by twisting. 4. Connect the wire last. The bulb is type D2S. Use a known brand, because unknown bulbs may fit the reflector poorly.
What should be noted when replacing the passenger-side bulb?
On a car built before the facelift, the front part of the air filter housing must be removed on the passenger side. The plastic ring of the bulb's retaining ring can turn to the wrong position and prevent installation.
Are there separate relays or fuses for the xenon lights?
No. The lights are controlled by the light module, which is in the driver's footwell next to the steering column. Fault code 9CBC points to this light module.