M818 Stop light problem-NEED HELP!

[Autocar]

I just won an M818 and got it home. Have a weird problem with stop lights that hopefully someone can help with. The rear turn signals work on both sides(L & R) with the headlight switch in both positions- Service Stop and Service Drive. The problem is that the R Stop light works correctly in both headlight switch positions, but the L Stop light doesn't work in either postion. I don't have a wiring diagram, but I figure that since the stop and turn bulb are the same, if one works , the other ought to work. Any ideas?

 

[gimpyrobb]

Check the ground on the one that isn't working. Aren't they dual filament? Could one be blown out?

 

[Autocar]

Checked the bulbs. Both filaments good. There is only one center pin on the bulb so the filaments are redundant. This means that for some reason power does not get to the bulb.

 

[gimpyrobb]

Do you have voltage when the peddle is pressed? Could it be a short or cut somewhere?

 

[cjtroutt]

I would check the Ground & the signal stat switch May have corrosion problem.
Just went through this on M915A3 That was in an flood water Detroit Diesel S60 500Hp
it was an mess Grounds & lots of dielectric grease to fight the problem.

Can be in the cab wire connectors.

 

[nk14zp]

Check your blinker switch.

 

[Autocar]

What do I check on the blinker? Does the stop light go thru the blinker switch?

 

[bigelk50]

Make sure that the blinker switch had a good ground to the steering column. It grounds by the clamp that holds it on. Then check the contacts in the switch. sounds like a ground/contact problem.

 

[gimpyrobb]

He said he has one of the lights working. That means the circuit is active, just one housing isn't working right. Check for voltage with the peddle pressed.

 

[cranetruck]

I just won an M818 and got it home. Have a weird problem with stop lights that hopefully someone can help with. The rear turn signals work on both sides(L & R) with the headlight switch in both positions- Service Stop and Service Drive. The problem is that the R Stop light works correctly in both headlight switch positions, but the L Stop light doesn't work in either postion. I don't have a wiring diagram, but I figure that since the stop and turn bulb are the same, if one works , the other ought to work. Any ideas?

Here you go (wiring diagram).

On plastic housings, both mounting screws must be grounded.

 

[Autocar]

Thank you. I will check the wiring tomorrow