Headlight problem, and it's not the lamp

[SLO C5]

The low beam, driver's side headlight is out on my 89 Sub, it has the dual horizontal headlights. All of the other lights on the driver's side harness work fine, the front and side markers/turn signals, and the high beam work as they should. I went over to Kragen and got the replacement halogen lamp, $12.99, and installed it. Still nothing.

I pulled back the wrapping on the wire harness a few inches from the light socket to see if the wires were damaged, but everything looked OK.

Also, what is that ~4" diameter canister tank thing up by the driver's side headlights? It has a line in it that goes near the power steering pump, and one that goes into the throttle body area.

 

[frankin5]

The low beam, driver's side headlight is out on my 89 Sub, it has the dual horizontal headlights. All of the other lights on the driver's side harness work fine, the front and side markers/turn signals, and the high beam work as they should. I went over to Kragen and got the replacement halogen lamp, $12.99, and installed it. Still nothing.

I pulled back the wrapping on the wire harness a few inches from the light socket to see if the wires were damaged, but everything looked OK.

Also, what is that ~4" diameter canister tank thing up by the driver's side headlights? It has a line in it that goes near the power steering pump, and one that goes into the throttle body area.

charcoal canister for the smog. It recieves the fumes from the gas tank.

 

[trikstark5]

Wire the headlight straight to the battery without using the harness and see if the light turns on. If it doesn't, time to pull out the DVM or light tester and start checking for voltage to the socket for the light.

 

[AZ79K5Project]

Do you have a DVM? Check the voltage at the plug for 12 volts and check the ground at the plug to ensure you have a good ground.

No voltage - bad wiring - check continuity
no ground - broken ground wire - easy fix.

 

[Mike D]

Probably corrosion in the plug, which was a odd pin type design. My left headlight plug ( same type) kept comming off the headlight (poor design). Had to rig it to stay on.

 

[idislikeunc]

my ground wire on that side always came loose from wheelin

 

[burban89]

+1 on the corrosion, I had the same problem on my '89. The socket was bad, the contacts were about gone. I replaced it and havent had problems.