Operation CHARM: Car repair manuals for everyone.

Headlamp: Service Precautions






HID Headlamps, Usage and Safety Precautions

Never replace bulbs if you are not familiar with the procedures, safety precautions and tools.


Danger to life due to high voltage.

Always disconnect the battery ground cable before working on gas-discharge headlamp components marked with yellow high-voltage symbols.

Then switch low beams on and back off. This removes any possible residual voltage.

Turn off the ignition and all electrical consumers and remove the ignition key.

The gas-discharge lamp control module should not be operated without the gas-discharge lamp.

Due to the high voltage (over 28000 volts when igniting the lamp), the gas-discharge lamp should only be operated inside the headlamp housing.


Risk of injury due to burning, Ultra Violet (UV) rays, blinding and explosion.

Due the high temperatures, absorption of UV rays, and the risk of blinding, the gas-discharge lamp should only be operated inside the headlamp housing.

Do not look into the beam of light. It may interfere with the ability to see for a significant period of time.

Gas-discharge lamps are under pressure and can crack when bulbs are replaced.

When removing and installing HID bulbs, always wear safety glasses and gloves.


Pollution risk.

Gas-discharge bulbs require special disposal. They contain metallic mercury (Hg) and traces of thallium.

Do not destroy gas-discharge lamps. Avoid contact with burst glass bulbs.

Follow disposal requirements, only dispose of gas-discharge lamps in suitable containers at an authorized collection site.


Do not touch gas-discharge bulbs with bare hands. The remaining fingerprint would evaporate due to the heat of the operated bulb and condense on the reflector which would impair headlamp luminosity. Use clean cloth gloves to insert the gas-discharge lamp.

Only replace faulty HID lamps with the same type of lamp. Bulb identification can be found on bulb socket or glass cone.

Harness connectors must engage correctly when installed and must be checked for proper connection.