Low beam testing procedure 1984

[PK 77 911]

I need to test the low beam circuit. I have high beam but no low beam. I am trying to figure out if I have a switch problem or if the headlight low beams are burnt out.

Anyone know how to do that.

Thanks

[r55forme]

I can give you a starting point--I recently installed the jwest relay and the output wires to the left and right headlight are white (Fuse 7 or 8) and yellow (Fuse 5 or 6) when you count #1 at the front of the car. You can trace it back from there to the switch, but verify you have power there and work your way back to the switch. Make sure those fuses are good and the wires are connected before you move to the switch.

[EC900]

Good point on the headlamp relay upgrade, get one. Also I’ve found loose wire and dirty fuse terminal connections when searching gremlins.
https://www.jwestengineering.com/assets/images/Instructions/911_HL_relay.pdf

also has a youtube tutorial.

[zuch]

Disconnect the source (top) of the low beam fuse. Take a jumper from battery positive to the top of the fuse you just removed the wire from. If the lights light, you have a problem upstream of the fuse. If your ligths don't light, you have a problem downstream of the fuse.

[PK 77 911]

Thanks for the reply so far. I’ve determined the lights do work high beam low beam when removed from the car. Other than just the low beam not working. I now have an intermittent issue with the lights coming on at all.