Instrument Panel lights on Auto Lamp not working...

[alchemist]

Recently, I noticed that when I have my Auto-Lamps on (i.e. the lights come on when the photosensor senses that it is dark outside), the instrument panel lights do not light up. The headlamps come on just fine. In order to get the instrument panel lights to come on, I have to actually pull the light switch knob out, basically running it in manual mode. Would this be a problem in the actual headlamp switch itself??

Thanks for any help.

[tjc78]

This was the symptom on my 89 MGM a long time ago, and yes it was the headlight switch. It could also be the harness is damaged/melted.

[alchemist]

This was the symptom on my 89 MGM a long time ago, and yes it was the headlight switch. It could also be the harness is damaged/melted.

Thanks. How hard is it to replace? Does the IP panel front have to come off?

thanks again.

[sly]

yes... front panel has to come off... which I think goes across the entire dash like the aeros. pop the mid trim off and remove all the screws for the tabs that go up. don't forget the screws in the instrument cluster area too (should be two upwards of the cluster). Once that is all out of the way, it should just be 4 screws to get the switch out. The bugger part is getting the knob off the headlight switch. some have the quick release spring in them (small flat screwdriver in the notch at the base of the knob will release it from the shaft). Some have set screws (T6 will work... not sure the hex key size though... it's actually a hex key set screw if that's what's in there). on the off chance you have one of the bastard ones that has the knob glued to the rod, you will have to press the release button that's on top of the headlight switch from behind the dash and that's a royal pain in the ass and impossible if you have fat arms. The secondary knob just slides off.

[tjc78]

Thanks for answering Slymer, I've never dug into a 90/91 dash.

[alchemist]

yes... front panel has to come off... which I think goes across the entire dash like the aeros. pop the mid trim off and remove all the screws for the tabs that go up. don't forget the screws in the instrument cluster area too (should be two upwards of the cluster). Once that is all out of the way, it should just be 4 screws to get the switch out. The bugger part is getting the knob off the headlight switch. some have the quick release spring in them (small flat screwdriver in the notch at the base of the knob will release it from the shaft). Some have set screws (T6 will work... not sure the hex key size though... it's actually a hex key set screw if that's what's in there). on the off chance you have one of the bastard ones that has the knob glued to the rod, you will have to press the release button that's on top of the headlight switch from behind the dash and that's a royal pain in the ass and impossible if you have fat arms. The secondary knob just slides off.

Might it be a good time to replace the odometer and trip gears since dash trim is off? There is probably a detailed write-up on this in the forum.

Thanks guys.

[sly]

it might be... but if they still work... don't worry about it. Those things are rather troublesome to get at. If they are having issues, then yes. But once you've taken that all off once or twice, it gets really easy to get at.

[alchemist]

it might be... but if they still work... don't worry about it. Those things are rather troublesome to get at. If they are having issues, then yes. But once you've taken that all off once or twice, it gets really easy to get at.

They stopped working back in June of this year. Just found a writeup on the www.odometergears.com website. You're right, it would be a day job. and those gears are pricey. you need both sets (trip plus odometer).

[alchemist]

Update - Instrument Panel lights on Auto Lamp not working....

A while back I posted that when I have my Auto-Lamps on (i.e. the lights come on when the photosensor senses that it is dark outside), the instrument panel lights do not light up. The headlamps come on just fine. In order to get the instrument panel lights to come on, I have to actually pull the light switch knob out, basically running it in manual mode. I asked if this would this be a problem in the actual headlamp switch.

Everyone said "yes", but I replaced the switch today and no luck. so I did some more scientific study on the circuit of the AutoLamp funtion and I believe it's the AutoLamp Relay that is the culprit. Why? Because back when I first posted, I said that only the instrument panel lights don't light on AutoLamp. But doing a check today, I fould that also, the 'other' exterior lights don't light either (tail lamps, parking lamps). The Tail, parking and instrument panel lights are controlled separately from the headlamps, by the AutoLamp Relay. Are these still available??

[gadget73]

yeah, its the autolamp relay. I didn't see this when it was posted.

Unknown about availability, but if you're really careful you may be able to open the existing one up, polish the contacts up, and make it go again. Unfortunately if they are badly burned, it probably won't stay working for long.

[sly]

AZ has the weird relays. My 82 Mark has all new relays now. They don't have the sensors though. Just take the relay in with you to your parts place... they'll find the right one.

[sxcpotatoes]

Where exactly is the autolamp relay (& maybe the front/parking lights relay as well)? Had the burnt wiring harness on Electra, my blue car, replaced & finally had front & rear parks for the trip home from mechanic then BAM, fronts gone out again, luckily still have rears. >_< Turn signals still work.

I have the electrical/vacuum troubleshooting manual but haven't had time to track the relays down.

[alchemist]

Thanks everyone. I think I found the relay- RLY133. Made by Standard Motor Products.

[sly]

the autolamp relay is under the hood on my Mark in that cluster of relays be the cruise servo. No clue where it is on the other cars since those still work. The parking lights don't have a relay (they should) just like the headlights.

[alchemist]

The relay on the CV's and GM's looks like its on the steering column, right side. I think all you have to do is to remove the shroud.