GMC high beam/low beam issue

[mrlobster]

i just finished putting fresh headlights and some additional grounds on my 72 GMC. Now, when I turn them on the passenger side low beam is off, and the driver's side comes on. When I turn on the high beams, all four come on as intended. Any ideas?
Thanks!

[Mator]

I just had the same problem. Low beam was not working on driver's side. Replaced the dimmer switch because it wasn't switching when pushed and had to replace the bulb too. Works now but had to buy passenger side because the color was different than stock. Anyways, low beam might be blown. Even if they are new. Try switching them.

[Stocker]

Start by using a test light or a VOM to check for 12vdc at the terminals.

[centuryhouse]

I just had the exact same thing happen, and it was just the harness / plug in at the passenger light that wasn't making contact well.

[burnin oil]

Most head light harnesses are a single feed wire to the headlight then jumped over to the other side. This takes the switch out of the equation. Check the connector for wear, corrosion, or a bad splice. Those repair connectors from Azone are pretty cheap and have under sized wire. If this is good then follow the pigtail back to where the wires are connected and you may find a break or a lot of corrosion. Odds are that if it worked before the headlight were switched that the connector was damaged while reinstalling the headlight.