DIS, VMM or ECM problem?

archerman0531

Registered User
As I was driving home tonight I noticed that my change oil moniter was off. It had been on and I just happened to notice it was off, like usual, my tac wasn't working as well.
So I'm driving along, I notice that the oil chane side lights back up, tac starts working, and lights flash just a bit brighter all about the same time.

Is this just a coincidence? Or are these all some how on the same circuit?

And another thing, I don't think my cooling fan is running, it never gets hot, but I've never seen it on before, and I'm pretty sure it should be whenever ive had the hood opened with the car up to operating temp. I haven't done much trouble shooting electrical wise, I should be able to hear it kick on correct?

Thanks for any help!
 
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The oil thing on the VMM is probably the VMM, but could be the DIS since you're dropping the tach signal. The VMM counts engine RPM so the coincidence seems interesting. Its always a good idea to have a spare known working DIS on standby for trouble shooting.
 
If your A/C works, try turning it on and the fan should kick in. That will tell you at least it works and gives you a way to make it run just in case it starts to overheat. I dont recall though if the EEC will engage the fan for the A/C if you're low on refrigerant.
 
Ok, I'm really not sure what's Wong with the tac either, I can be driving along just fine, an out if no where it just drops. 10-15 min later while I'm stills roving the smart speed it just picks right back up. And does this even more so once it gets up to op. temp.

And the VMM I got from a junk yard. So deff. Possible that it's going bad. But it was still in the dash and all in one peice and all the windows and doors were sealed, so I thought it would be the best one.
The one that was original to the car, it's front face broke and I was driving down the high way and it slid out a little, I didn't think anything of it until I started smelling something got and realized That it was smoking and sparking. The contacts on the board were grounding out to the radio frame. So, I kinda fried the original one.
 
The ac compressor doesn't kick on at all. The guy I bought it from said he just had the whole system refreshed and refilled. I drove it when it was 20 something degrees outside, so couldn't tell by the temp. If it was on, and there was no fogging on the windows when I had the defroster on so I didn't even think to turn it on and pop the hood to see if it was working.

My father in law is a ac guy so he said he will look at it here in a bit.
I never got certified thru ford to do ac at the dealership I worked at, so I'm not to familiar with refilling the system or checking it. I mainly just helped someone who has been doing ac for 20+ years hook it up and he tried to teach me some on ac, but That's about all I ever did with ac.
 
Found out the cooling fan does work, Just had never seen it on, nor heard it before now. It's very quite compared to other cars with electric fans.
 
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