Our Fast Fit wiring harness includes high beam adaptors for the two most common 4WD headlight globe sizes: H4 and Hb3/9006. This quick guide shows how to wire the high beam feed to other high beam socket styles.
- Wire Strippers or equivelant
- Soldering Iron, Heat shrink/Electrical Tape
Disclaimer: When in doubt consult a professional. Poorly executed wiring may lead to injury or damage of property.
Remove input socket on Fast Fit wiring harness to expose wires. Remove outer insulation to expose the wires and approximately 2-4cm of each wire insulation. (Ensure enough outer black insulation is removed to work with the inner wires and separate them).
Locate the high beam globe in question. Remove the insulation without cutting the wire strands.
Depending on your headlights, the wires may be labelled negative – and positive +.
There are a few ways to determine which is which as the polarity must be correct.
Method A) Set your multimeter to Voltage DC mode, attach the multimeter probes to the exposed wires on the high beam socket, activate the high beams and view the multimeter reading. When the reading is 12V Positive the high beam wire leading to the positive terminal on the multimeter is the positive high beam wire. If it reads negative, switch the probe wires around. Ensure the exposed wires do not short circuit during this process.
Method B) Perform a continuity test with your multimeter to find the negative wire. Attach one probe of your multimeter to one high beam wire and the other probe to a ground on the car. When the the multimeter shows continuity the probe is attached to the ground/negative wire on the high beam.
Wire the Fast Fit wiring harness high beam input wires to the headlight high beam socket wires. Solder and finalise with heat shrink and electrical tape.
You may need to cut a slit in the headlight dust cap/cover to feed the wiring through first before connecting, leave some extra slack to allow for easy future removal of dust cover. Seal drilled holes/slits where necessary.