corellian vette

Hey everyone!

So you'll see me post about a parts car frequently for the next few days.

I have an early '86 manual car. It's rough but the bones are good and I'd like to see if I can get it back on the road.

One thing I'm curious about are the warning lights on the gauge - the ones that light up before you start the car; (Washer, Belt Tension, Stop Lamp, etc.)

I got nothing. Rest of the gauges work fine. I know it's not the cluster since I tested it in another car.

Any ideas?

The Forgotten On

Ignition switch failure.

It's a classic symptom along with the the lights doing the exact opposite and staying on long past starting the car.

WallyP

The cheap replacements seem to be suspect - pay for the OEM.

worf928

Central Warning Computer. Its under the dead pedal. There is a troubleshooting guide on the workshop manual cd-roms. Or, just pull it and look at the board for melted resistors.

Lower probability: alternator. A very long time ago I had an 86 towed to me with two symptoms: not keeping battery charged and the warning lights would flicker but not light-up. I fixed the 'easy' problem with a rebuilt alternator and the head-scratcher went away too.

Alan

If the alternator resistor & lamp (in the instrument cluster) are missing or damaged the car doesn't know to go into bulb test. If the alternator exciter line is shorted to (30) positive power - the bulb check will be immediately cancelled (so will never start).

So easiest check is to ground the exciter wire at the CE panel or at the 14 pin engine harness connector. If the warning lights come on (I think they will) then you have an alternator issue (likely just the regulator).

To test on an '86 ground pin M13 or L23 on the CE panel plugs (3rd pin up on left side of plug M OR 3rd pin up on right side of plug L. It must already be grounded before you turn the key to Accessory position.

Alan

Mrmerlin

any updates?
I have a1988 S4,
no warning lights on the dash except for,
the alternator charging lamp and the anitlock light come on when the key is turned to run.
after start the alt lamp goes out and the gauge shows a charge,
then antilock lamp also goes out after engine start.


all the gauges work as they should just no warning lamps
Alan any suggestions?

I swapped in another computer from an 86.5 and no lamps when turning on the key.

Car has also had an aftermarket alarm installed that I have removed,
and I think I have all the wires reconnected properly.

M. Requin

I had this same problem with my 86.5, and Alan's advice, repeated above, solved it.

Mrmerlin

Hi Martin could please explain exactly what you did? more detail is better Thanks!

M. Requin

Sure- IIRC (that's really hopeful...) I had the instrument cluster out, so I made sure the ballast resistor was in place, connections good, and that the alternator lamp was good. All ok there, so I went on to the alternator exciter wire. It looked OK at first, but after looking closer, there was no continuity to the 14 pin connector. I added bypass wires from the alternator to the 14 pin connector, and that corrected the problem. I hope this helps, sketchy as it is.

Captain_Slow

I'm just thinking about where we'd all be without the internet and posts like this (and Martin's details above).

Alan

Stan,
Since your alternator charge light works normally - it is not either of the classic causes: missing components in the cluster for the resistor/lamp or a broken alternator regulator (or open circuit in the path).

Note that the alternator lamp and the gauges are supplied differently from the warning lights. So first check fuse #10 the supply for the warning computer (valid on an '88 other years vary).

Alan

Mrmerlin

OK thanks i will let you know what I find

Mrmerlin

Alan thanks for the suggestion.
OK checked fuse 10, its good,also swapped in another,
no warning lights come on with the key in run position.

when fuse 10 is pulled out with the key on,
the turn signal flasher clicks fast and the long " I " lamp on the pod flashes fast with the green turn signal lamp.
I tried swapping in two different cancel button bars but nothing changes.
Whats causing the TS relay to click fast.
I just need some guidance on how to test this unit and where to start,

the alt lamp lights up and the antiskid lamp does also, when the key is in run position these both go out when the engine is started
I found the one of the door lock fuses was blown

worf928

You swapped-in a known-good Central Warning computer (from under the dead pedal?) from anothe 928? Yes?

Mrmerlin

Dave I have one from my 86.5 parts car the part numbers are different,
I did swap it in but no joy,
and I dont know if the part I swapped in was good.

I checked fuse 7 and the grounds on the black 15 and yellow 11 connectors both are good
I have another option i will be back.

OK might be onto something,
I put the not working computer into my 88 5 speed and the warning lights dont come on,
so this tells the computer is bad.

I am reluctant to try my 5 speed computer into the non working car for fear of smoking it