Need help with 2 minor electrical bugs

[patrick1151]

I have two issues that have me stumped. I have no power going to either my windshield washer pump and my dome light. Everything else works and no fuses are blown. The wires going to the pump motor appear to be fine, not cut or anything but I havent traced the wiring for the dome light yet. The only other thing with the dome light is the switch in my door frame could be bad as my door open buzzer comes and goes. Thanks for any suggestions and this is on my 77 Astre wagon.

[cjbiagi]

Most likely 2 different problems. The dome light could very well be the door switch. Does the dome lamp work when you try to turn it on with the headlight switch?
I assume the w/s wiper motor works ok? This would indicate that you have power going to the wiper switch which of course also powers the wiper motor pump. Could be a bad switch, loose wire on the switch or a bad ground.

[patrick1151]

the dome light does not work off the headlight switch either. I did switch the bulb in case it was bad and then put a tester light on the dome light and there is no power there. Same thing with the pump when the headlight switch is on and when you push it for the pump, there is no power going to the pump.

[my79monza]

The power for the dome light comes from the fuse box marked CLK-LTR-CTSY it is located on left side second down from top.
Left side of fuse is power in right side is power out to clock-lighter-dome light.
when checking for power check on the fuse clips not the fuse as sometimes the fuse won't make connection to the clip, the tester will confirm this if it is checked at the clips.
Merle

[patrick1151]

I had tested my lighter with a tester light as I wasnt sure if I had power there, I dont ve a cigarette lighter in the car but there definitely is power to the cigaretter lighter. I guess I will have to pull the trim and everything off and check to see if the dome light wire has been cut. Thanks.

[my79monza]

I have the headliner out of my 80 Monza and I can tell you on it the wires run accross the top and down the drivers side windshield post.
My 76 Monza wiring diagram shows a connector block between the dome light and the wiring splice, check behind the drivers side kick panel.
I can't see where there would be an issue between the dome light and the windshield post so that would be a good place to start, betwen the post and kickpanel.

Merle

[patrick1151]

Thanks Merle. This car is full of gremlins at times. I know I have a short or wires grounding from time to time that causes the fuse for the dash lights+tail lights to blow. I know where the issue is but it is hard to get at to fix. I wrapped some tape around the bare wire for now but it lew again today, ad that to my list of things to do. Also I occasionally lose my high beams ike right now but that seems to either be a bad ground/ground issue or bad headlight plug. Len had them working a few weeks ago but the high beams went out again yesterday. Sometimes I wish I had just crushed this car.

[my79monza]

I can tell you this from experience that if you need to do anything under the dash just pull the drivers seat out, takes 5 minutes and makes a world of difference, not good mind you but a lot better.
Merle

[starfire383]

Replace the door switches before you go chasing a bunch of gremlins. The thing about electrical bugs is if you have reason to suspect one component it's a complete waste of time to look elsewhere. They ought to call it an electrical octopus since a single bad component has tentacles that reach out to glitch anything sharing power or ground.

Bare wires have probably oxidized from exposure and could be hiding broken conductor strands. Wires and switches are just mechanical components, the problem comes when people view them thru a cloud of mystery because they're electrical. The harder something is to access, the more likely it's to blame

One other thing...without a headliner many GM dome lights will short to the roof.

These old headlight switches have decades of carrying the headlight's current. If you can't afford/find a new one, pull it out and hose it with electrical parts cleaner while working the mechanism about a hundred times. Both rotation and pull. Allow to dry. When you reinstall, add a pair of relays up front to take the headlight's load off the switch. Car's lighting and electrical performance will jump significantly as the headlight load is removed from the wire which supplies interior power.

[patrick1151]

I replaced both the headlight switch and dimmer switch to no effect. I dont have a spare door switch but I probably can get one. I am busy looking for work and havent even tried to tackle this yet, Thanks for the info