Ac help

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So my ac fan 1 is not turning on when we “hot wire “ it the fan turns on then it gives us ac but when we don’t have it hot wired and we just try the relay it does not turn on we tested the relay and it click on and off but could it still be faulty and also could it be that the power ground wire from the ecu to the relay has a short and not giving it the power it need to fully turn on and make the fan run

 

[HemiLonestar]

Holy run on sentence. Relays aren't expensive, did you try replacing it?

 

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Haha yea sorry wrote it quick cuz I was at work and no I didn’t I’ll have to try a new one and see

 

[HemiLonestar]

Hell, do what I do, find them in the junkyard. That's how I keep spares.

 

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Well we tested it with a 2nd relay and no luck I think I need to get a wiring diagram

 

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What one is the power train control module and where is the pin hole located

 

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What wire is for the power train control module

 

[SYKRAMMAN]

What wire is for the power train control module

View attachment 137486

I’ll put my pay check it’s your tipm(fuse box) they are known for failing. Check if you have power out of the tipm going to the fan. I highly doubt it’s a pcm issue.

 

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We don’t have a ground signal to the relay

 

[SYKRAMMAN]

We don’t have a ground signal to the relay

Definitely the tipm, I just got through dealing with this on my 02 4.7. it was one of many issues with tipcm’s I’ve had, went through 5 before I found one that all relays and fuse work.

And every one it was the same problem, not grounding out!
They don’t make them new for 02 so I had to junkyard them. But after 02 they still make them.

 

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So can u get inside it instead of buy a whole new fuse box

 

[justin13703]

So can u get inside it instead of buy a whole new fuse box

Just wire up your own relay using the 12v going to the ac compressor as the trigger. That’ll be a hell of a lot simpler and cheaper than replacing the tipm.

 

[OCDTech]

Just wire up your own relay using the 12v going to the ac compressor as the trigger. That’ll be a hell of a lot simpler and cheaper than replacing the tipm.

Bingo.