1978 Interior courtsey light problem

[8kgold69]

Hello
Okay. I will try to explain the issue with my car the best I can.
1978 with an interior light problem. 1st the interior lights don’t work, UNTIL I plug in the little white delay timer box, which is mounted behind the glove box, with a circuit board inside. I know the box is the timer delay for the courtesy light package. The interior lights work correctly with the door jam pins. Doors close, the lights go out. Open either door and the interior lights come on as designed. However, I’ll start the car and let it run and then when I turn the engine off with the key, the engine continues to run WITH the ignition off and the key out of switch. If I unplug the interior light delay timer the engine will shut off. The other odd electrical issue with the car is with the A/C relay. The relay is located under the hood and is mounted to the firewall by the evaporator case, has 3 wires that plug in at the top and 3 wires that plug in at the bottom. The 2 top wires for the top plug has a blue and a red wire. The red wire is the main hot feed wire. With the engine and ignition off and the key out of the cylinder the red feed wire still has power.
This car has 5K miles and is all original, including the tires, belts, hoses, etc... NO modifications, but the car has sat a lot.
Could another relay be bad? Could it be the delay interior light timer that is bad causing all the problems?
Any suggestion is a help.
Let me know if you need more details. I don't know what else to add.

 

[bill81vette]

Start by checking your wiring...
If this vette has sat around alot,
Then perhaps mickey's cousins got to it and chewed some wires.

 

[melsy]

I owned a new '78 back in the day and did all my own work. First, if you don't have a shop manual, get one fro www.helminc.com They print it for GM. Interior light relay. I checked my manual and there is no reason I can see for your engine to run on. Totally different circuits. Previous thread about mickey may be in play here--not to mention possible ground/corrosion issues after sitting all these years. The relay I think you are talking about is not the AC Relay as you called it--but the high blower relay. I wouldn't worry about it if the AC and blower are functioning. Frankly, aftyer sitting all these years and only 5K miles--this car will probably need quite a bit of sorting out to be a safe driver. Hope this helps.

 

[8kgold69]

Thanks for the response. The car has been kept in a climate control enviroment so everything is in good condition. I inspected the wiring harness and did not detect any damage. You are correct though regarding the relay. I ment the blower relay for the A/C. I will reinspect the wiring again to see if I missed anything.

 

[8kgold69]

I appreciate the responses to the thread. The mystery has been resolved. Believe it or not, NO I not Ripley's. Anyway the problem was the delay timer for the interior lights was going haywire. I replaced it with a new one from Corvette Central and problem corrected. I also had a problem with the rear window defrost. It was the relay. That's another problem. The defrost relay for the 1978 is a 1 year only relay. Did some searching and found one. Now I read some other threads where individuals were having problems with the defrost not working and they stated they could not find the relay. Well, it is hiden pretty good. You have to remove the drivers side kick panel, look up under dash, there are a bunch of wires, where the bird cage is welded the the frame, you will see the body to frame boltand you can actually see the back of the door pin for the courtesy lights and the 2 wires connected into it, if you go up on that metal frame piece, about an inch from the pin, there is a slot in the metal that the relay goes into. I hope this helps someone in the future.

Thanks