Instrument lights ground, where is it?

[HRH]

I'm at work right now, so I can't look at my wiring diagram. Not sure if that will help anyway. Have this odd problem in the 510. Sometimes when it's cold, I goose the throttle and the instrument lights on the stock dash guages and speedo go out, then they come back on after the throttle returns to normal. Doesn't happen all the time and doesn't affect anything else, don't lose spark or anything. Only seems to happen at tip-in, though sometimes under load they blink out for a bit, then come back on. Headlights still stay on, don't flicker, just the guage lights go out.

 

The car does have an internally regulated alternator on it, the 6 plug connector has two wires joined for the charge circuit, which works fine.

 

Dave at work here said might be a crappy ground if the guage lights ground through the dash. Certainly there aren't that many screws holding it on, but I'm not sure. I know where most of the other grounds are. The light switch is new, not stock, but another version we had in stock as a universal double pull light switch. It works fine.

 

Any ideas what that might be and where the ground is?

[zerow]

If its like a 610, there is a small stud above the hood latch assembly (well, not right above) along the kick panel on the driver's side and there will be a couple of black wires for the ground attached to the stud with a screw. Remove, clean corrosion, and replace.

[philcas1987]

If its like a 610, there is a small stud above the hood latch assembly (well, not right above) along the kick panel on the driver's side and there will be a couple of black wires for the ground attached to the stud with a screw. Remove, clean corrosion, and replace.

Nailed it !

[HRH]

Interesting, I shall look for that! Thanks!

[hang_510]

does it flicker with the key on and engine off?

 

 

check the actual switch and connector.

the main wire plug(like a vacuum tube base) is also a place to check for corrosion.

[HRH]

Tightened it up today, lights still flicker. Rather intermittent. Didn't do it the whole time I was driving except once during start up, then was fine. I'm sure they'll do it again though. Might have a crap ground from the back of the guage cluster too I suppose.

 

No, it doesn't flicker with the key on and engine off. Switch is new.

[izzo]

this is not relevant to anything, but :D

 

[zerow]

Tightened it up today, lights still flicker. Rather intermittent. Didn't do it the whole time I was driving except once during start up, then was fine. I'm sure they'll do it again though. Might have a crap ground from the back of the guage cluster too I suppose.

 

No, it doesn't flicker with the key on and engine off. Switch is new.

I'm going to go out on a limb here, have you checked the ground going from the battery to the block? Remove and check it. There is also another one that runs near the battery, handles the ground "connection" to the unibody of the car. It has a chunky looking Phillips head screw on it that can get corroded like crazy. I ended up running additional grounds all over the place, including splicing the ground behind the cluster and running one to the other stud on the other side of the passenger compartment (trust me, there is one there as well...) just to make sure I had plenty of grounds hooked up.

[HRH]

Yeah, battery and cables are all new, with additional ground straps. It did it before I switched all that though.

[HRH]

Izzo, like the blue look!