I really appreciate your help. For info purposes, The IPD kit that I installed did not have a harness, just the H4 lamps and you splice in the new female bulb sockets. They have worked fine for more than a year. So it is the original 1990 headlight setup. Now, only the passenger side low beam works and I’ve tried different bulbs in each, so it is not the bulbs. Remember there was evidence of melted wires at the crimping points on this side.

Tonight I tried my best to diagnose with a test light. There is no power for the low beam on the driver’s side at the socket. The high beam and ground check out fine. One of the blue wires at the bulb out canister under the dash had no power. The main headlight relay wires all lit up the test light except for the ground. I can hear the clicking of the main and the bright dip switch relays respectively. I am not sure what to check at the dip relay under the hood, but it is clicking. What to do?

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1990 240- 245K- Original Owner-M-47, VX cam, IPD sprt springs, bilstiens, spt exh, euro lamps-turbo whls,- still slow but handles well- Near Houston