Just done flustered

[Ataritoys]

So.. Being a 78.. I expected extra draw when I hit the head lights.... Last night when I turned the head lights on, I suddenly got a 4v drop and dash started smoking.... again.
I'm not sure how much more rewiring I can handle. I checked the wiring I did. It's all fine and in tact. I haven't taken the time yet to try to trace back any more wires. I guess it could be wiring to the voltage meter or wiring from the lighting system?
Anyone have a common failure point for me to start at?

Thanks in advance

[Dave Colangelo]

Im not sure about the 78 924's but I know my 78 911 does not have a headlight relay it runs all the power though the switch. It is very common to change this set up and bury a relay under the hood somewhere. It will make it safer and protect you from things like this. You may also be using improper gauge wire. When it comes to hooking up things like this I always over shoot the gauge a bit to be safe. If there is 18 gauge from the factory I will use 16 in its place just to be safe. Are you heat shrinking all your connectors? Are there any exposed tabs on the back of the connectors? The volt meter should be in parallel in your system. If the dash started smoking I smell a short of some kind, a bad one at that. Did any fuses blow?

Regards
Dave

[Ataritoys]

not a single fuse blew. after she started smoking I turned off the light switch, stopped smoking. I figured a short in dash with the head light system. well melted wires now lol.

[Jrboulder]

Aww shucks, your rig done busted.

Dave, it's funny you mention adding a relay. I just had that "upgraded" relay fail last night.

As you can see here there is a relay (J) for the highbeams (part of L1, L2) on the 924 but it still sends all the load through the headlight switch, just not through the dimmer switch like on the 911.

E1 is the headlight switch and E4 is the dimmer switch. Obviously the low beams are not on a relay.




I think headlight switch failure is pretty common on the 924 and early 944 because of the reasons Dave mentioned.

The first thing I would do would be clean every ground and connector you can get to.

Our host sells new headlight switches for $52 and they have them in stock.

[Ataritoys]

I will check it out when I get home today. I hope thats all it is! It would make my life much easier.
I am kind of to the point of fixing the head light problem and letting her go.. I have had issue after issue with this girl. This love hate relationship--- some times just doesn't count lol

[kdjones2000]

I would check your J relay. The one on our '78 924 was dead (but it didn't cause any smoking). You might be able to bend contacts back and get a low enough resistance connection so it doesn't do it again. We did.