Well i wired a fan on a relay, i am using a ford tarus electric fan, and i have a switch on the igntion side and it signals to a high amp automotive relay that connects power to the high speed on the fan. i have had it on there for few days and i drove it fine yesterday all day. I woke up this morning and cranked it to go to church, well with i switched the fan on my tach switched back to voltmeter, and the gen light can on?????? what caused this it was prefect yesterday, and now with the fan off its fine. Can some one help me or tell me how to wire the fan correctly. thanks robert

 

help?

 

come on i know people have knowledge in the electrical field on these cars and i know people have put in fans so a little help, i have searched and found nothing of this problem
please any one robert

 

Explain this part better. I'm not understanding what you are trying to say.

 

It sounds like he has an SA, which has a combination tach and voltmeter. When the engine is not running the tach is a voltmeter.

The only time I've had this happen to me, the alternator was faulty. My quiestions would be, where did you get your powerfeed for the fan (did you take it from the leading coil?)

 

no the power feed i took off the battery, i keep blowing fuses else where, and i have gotten rid of the external regulator and i have a 89 alternator, but yes this is a 79 sa good call

 

can we wire it to the trailing coil for power and will it only work when the cars runnin?

 

The trailing isn't used all the time on the SA's. If you run the + signal from the leading coil to the relay and have the main power for the fan come off the battery, fused of course, it should work. Unless it's feeding back though the tach. Might be time for the 2nd gen fuse block upgrade under the hood.

 

is the 2gen fuse box a straight up boltin where the origanl one is?

 

Takes a mounting bracket and minimal wiring. When removed from the donor car, cut the wires coming off the fuse block as long as possible.

ReSpeed makes a bracket for this mod, I make my own.

 

im thinking its like you said its feeding back through. It worked for a while about a day or so and no problems , now all of a sudden im getting interferance. If i wired it with a relay to the leading coil, and a fusiable link, would i still get interferance. What is the deal with the 2nd gen fuse box never heard of it, will it stop my problems?? thanks robert

 

Where are you getting the switched side power from, is what I'm asking.

I'm wondering if maybe you connected it to coil negative, and this is affecting how the tach works... The coil negative WILL have positive voltage with the engine off, and you will also see positive voltage there with a voltmeter with the engine running.

 

i am pulling the switch voltage, from the fuse that supports the stereo and ac, its a 20 amp fuse, will that cause any interferance.