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So I'm having kind of a weird issue maybe someone has seen. Whenever I turn on the light in the car the temp gauge goes all the way up the tach drops and the battery gauge drops. Also the turn signal lights and bright indicator turn on. Not sure why that would happen I've never seen that before. Here's a link to a youtube video I took of it happening. I'm wondering if this is why the temp gauge reads so high right now even when the ECT reads fine and my autometer gauge reads normal.

Wow! I have an issue very similar to yours, I turn on the lights and the turn signals/high beam lights on the cluster come on but I also do not have any dash lights and my tach on my dash stops working. I never paid attention to my temp or battery voltage gauges to see what they do. I figure it's a ground or possibly a short somewhere, I haven't dug into it yet. I'll be interested to see what you find.
 

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Discussion Starter · #62 · (Edited)
The symptoms your car has are not typical for a multi function switch. Foxes did suffer from overheating headlight switch plugs and Ford had a fix for it by installing relays on both the high/low beams and fog lights. Often times; the headlight switch had a melted plug or internals. I'd definitely pull the gauge cluster and look for anything obvious. I'd also pull the headlight switch and do the same. As already recommended; check the cluster grounds.
I suspect Ford sent too much current through the headlight switch like they did with many of their vehicles. Ford is known for this in many of their older vehicles.
It might be the head light switch I want to say it's the original or that might be the hazard switch. I had them both disconnected recently so something might have happened when they were removed. The multi-function switch is new so I'm pretty sure it's good but I will look it over anyway to make sure. I also went through the grounds for the dash and made better connections for two of them.
 

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I figured out the problem with the lights it was a ground that got disconnected when I pulled the old EFI harness out of the car. The EEC ground and headlight harness ground were going to the same spot. I attached the ground and everything went back to normal.
Yay, glad you got it fixed. I can barely remember installing the system on my black car, but the speedometer didn't work when I first got it running. Turned out being a ground issue due to my rebuilding the transmission harness and eliminating "needless wires". Ooops.

Jay
 

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Yay, glad you got it fixed. I can barely remember installing the system on my black car, but the speedometer didn't work when I first got it running. Turned out being a ground issue due to my rebuilding the transmission harness and eliminating "needless wires". Ooops.

Jay
It's funny you mention eliminating the "needless wires." I did the same thing on another car. Oopsie!
 
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Discussion Starter · #67 ·
First autocross weekend with the Pro-M system went good. Didn't have any issues with the car. It did stall a few times after coming in from my run but it really wasn't a big deal. the car always started right up and pull really smooth. My driving could have been better but it had been a couple months since I last raced. But 5th wasn't bad for Saturday out of 30 cars probably shouldn't have hit a cone on my fastest run or I would have been third. I still have to hook up my autometer tach.


Now on to the fuel system install and crank trigger. Any of you guys running the Pro-M lower intake manifold have any thoughts on it?
 
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