79 L82 Auto AC car

No pop up lights, mine has fixed buckets. Lights work great. I replaced all of the bulbs and the flex board behind the center cluster, but not behind the Speed/Tach.

Interior dash lights don't work. Is there a quick way to test whether it's the light switch or the flexible circuit board board behind the clusters?
Just to test, can the light switch be jumped or overridden electrically to turn on the dash lights?

Thanks, Steve

 

Yes you can bypass
A jumper of 12 volts to your 5 amp inst lps fuse will be full bright--the fuse is in between the headlight stat and the bulbs

 

Good to know that it can be done but I'm not clear on how...could you please elaborate? I'm guessing that I need to pull the 5 amp fuse and run a jumper wire from a 12V source to the empty fuse socket? Or does the 5amp fuse stay in the socket and the jumper wire is sandwiched into the slot on one end? Can I use the accessory slots from the fuse block itself as the 12V? Any and all details greatly appreciated...

Many thanks, Steve

 

Providing the switch is not shorted you can leave the fuse in-but to be on the safe side since you are having problems remove the fuse.
Accy spade is fine but key will have to be "on" otherwise find constent soarce from another terminal.
With the fuse removed touch the left fuse holding terminal and this should light the dash lights.
The other or right terminal is what the switch stat feeds-With the headlight switch on if you put a 12 volt test light on that term. it should go bright and dim by turning the **** just like the dash lights.

 

Finally got to try this...I attached two spades to either end of a medium guage wire. One end I inserted into the "battery" slot that was open on the fuse block. I then removed the 5amp LPS fuse and slipped the other spade into the left side of the opening. With the key in accesory position I got voltage from the battery slot (~17V??)but no response from the instrument lights. Conclusion therefore is something is wrong downstream of the switch, between the fuse block and the instruments. I still need to test switch side of the fuse connection.

Weird thing though...you can't see into the slot for the LPS fuse since it's way up on the fuse block. The spade never felt like it was really inserting between the contact posts and would easily pull out. Is there a chance that the posts could be damaged and the fuse is never really making contact when inserted? What to look for?

Thanks, Steve

 

If you pull the center cluster out of the car you can test the lamps and it’s not real hard to get out. It might take you an hour or two. But you can also test the connector at the printed circuit for power to see if it’s making it up to the circuit board.

If you want to pull the center cluster out of the car, here is a link on how to:

http://willcoxcorvette.com/product_i...ducts_id=24531

Once you have this out, the fourth pin on the left (driver side) from the top of the connector is the power wire (20 gauge gray) to the interior lamps on the car. The first pin from the top to the right (passenger side) of the connector (14 gauge black) is the ground for the interior lamps on the car. Verify the ground, and verify the voltage on the pin connector.

Also check the the following:

Check the area where the connector plugs in to the back side of the printed circuit. The ears tend to come loose and not make proper contact when the connector is plugged in. If one of the flaps is loose and not making connection, you can super glue them back in place.

Check the printed circuit board. Run a continuity test across the connectors from one end of the connector flap to the end. You may have a broken wire in the circuit board.

 

i dont think steve has any lights at all which would lead me back to the switch or main power feeding the switch from fuse block, i know when my circuit board was bad on the speedo/tach cluster i still had center cluster lights.

steve if you need a hand i am off last week of this month and first week of september or we can try to
get a saturday again like last time.

 

Thanks for the great thoughts. About a year ago I had the cluster out and repaired all the gauges by swapping out the printed circuit board with a new one. Also replaced all bulbs. Everything works OK except for the lights of which I have none (Nothing behind tach/speedo, nothing at transmission...). I did not check for current at that point and I expect when I do I won't find any.

Things that work: Fasten seat belt light, turn signals, courtesy lights in glove box, overhead, and at feet.
Things that don't work: bright light indicator, all instrument bulbs

Don't know about low fuel or brakes because they haven't needed to come on. Is there a way to test the lights (ie should they all come on briefly when you first turn the key like in my DD)?

I plan to pull the cluster to frig with the lousy radio I installed so I'll have stuff exposed. I'll test circuit 8 at that point.

I plan on pulling the Tach/Speedo cluster to check it out and replace all the bulbs. Rich, you KNOW I'll be calling you when it's time for that! Let's get it on the calendar for late August.

Still curious...do the fuse contact posts go bad and how can I tell? The fuse seems to sit in the socket pretty tight, but when I tried to insert the spade to jump the fuse it wasn't. What then?

Thanks again...TBD,
Steve

 

My gauge lights went out and Zip had said it would be like 10 hours of labor to fix them. That was out of the question. I found the grey wire going from the gauge cluster and plugged it back into the light switch. I've been happy since. I was able to test the grey wire by plugging it into the yellow radio wires under the center console. The current is just right.

 

It would be unusual for the fuse clips to go bad unless you were leaking water inside the car and on top of the block. They could be corroded but should be fine! It wouldn’t hurt to do a visual inspection, but I don’t think this is your problem. Test the connector for current! Go to the slot in the fuse block and with the headlamps in the on position, test to see if voltage is present on the fuse. If voltage is present then the problem is in the wire between the fuse panel and the lamp! If no voltage is present, then the problem is between the switch and the block.

You can pull the fuse block loose from the dash by removing the outer firewall connections and then taking the bolts out. I’m not positive, but if the bulkhead connection is like the mid year and earlier cars, once you have it off the firewall you can split it in half to reach the actual wires and the fuse connections. I would not do this!

If the problem is in the headlamp switch, you should pull the cluster out! If the problem is in the wiring from the headlamp switch to the fuse box you still should pull the cluster.

Pulling the cluster makes testing so much easier and it would allow you to test all wires and connection points. If the problem is between the fuse box to the switch or from the box to the cluster connection having the cluster out makes it easy. I know you can take the screws loose from the dash pad on the side and force it outward enough to get to the headlamp switch, but you run the risk of cracking the dash pad and at the cost of a new one it’s just not worth the time saved.

If you guys do this on a Saturday night and need something, I’m usually on line Saturdays after about 7 (except next weekend) to help if you need it. I also have schematics that I can view should you need info. You can email me direct at willcoxcustomerservice@willcoxcorvette.c om

Willcox

 

I had my parking lights and my dash lights go out when I installed my after market radio (we had trouble finding the correct power wire, and I think we ran it to the light switch... thus blowing it). Using the service manual we found the ignition wire under the dash behind the radio, and ran it to a switch I put in the ash tray to power the wire feed from the light switch(the light switch is a P.O.S. anyways). Fixed everything... though the switch then decided that the interior lights needed to always stay on... so I pulled all of the bulbs to stop the battery drain.