Help - Engine cooling fans not working

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Chuff
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Joined: Thu Dec 20, 2012 5:28 pm
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Help - Engine cooling fans not working

Post by Chuff »

Hey all,

The engine cooling fans have stopped working on my wife's LS1 VX Commodore. I believe I have tracked down the problem and I'd like some confirmation of my findings.

The attached PDF contains the 2 relevant pages of my Holden LS1 manual and my diagnosis of the system finally led me to grounding terminal 30 of the low speed fan relay socket and the fans did not turn on as I believe they should have. I disconnected the engine cooling fans connector (page 1 diagram) and there is no continuity between terminal 30 of the relay socket and the ground terminals in the engine loom side of the cooling fans connector. As a result, I believe the wire between the relay socket & the fan connector has failed.

Is my logic sound and has anyone ever heard of this circuit failing?

And finally, how do I get to the underside of the fuse box? I've removed to bolts holding it to the car & unclipped the plastic center clip but I can only lift it up a few centimeters before I run out of length in the loom. Is there a trick to it?

Thanks.

Chuff
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LS1_Engine_Cooling_Fans_Circuit.pdf
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antus
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Re: Help - Engine cooling fans not working

Post by antus »

The logic sounds right to me. The ground side of the loom at the fan should link directly to pin 30 of the low speed fan connector block.
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Chuff
Posts: 267
Joined: Thu Dec 20, 2012 5:28 pm
Location: Melbourne

Re: Help - Engine cooling fans not working

Post by Chuff »

Thanks antus,

Now does anyone know how to get to the underside of the fuse box?

Chuff
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Holden202T
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Re: Help - Engine cooling fans not working

Post by Holden202T »

an easier way to test might be to make up some wires to plug into the relay and then run the suspect one directly to the fan and see if it works ? I know its a bit of screwing around but it might be easier than trying to get to the bottom of the fuse box.
Chuff
Posts: 267
Joined: Thu Dec 20, 2012 5:28 pm
Location: Melbourne

Re: Help - Engine cooling fans not working

Post by Chuff »

Holden202T, that's thinking outside the square. Excellent idea, but thankfully I figured out how to lift the fuse box up sufficiently to see what's going on.

Turns out the wire in question from the relay socket leaving terminal 30 wasn't Blue as detailed in the wiring diagram but turned out to be blue with a yellow tracer. I followed the wire and found the problem at the other end.
IMG_20161209_133832.jpg
Quick trip to Pick-A-Part and $5 later I left with a good as new replacement. Soldered it in and heat shrink the joins and problem solved.
IMG_20161209_165015.jpg
Thanks for the assist everyone.
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Holden202T
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Re: Help - Engine cooling fans not working

Post by Holden202T »

nice work!

I've heard a lot of stuff about the earlier ecotec sort of age cars had a lot of issues with battery and fan wiring not working too well over time, and the VT I think was the first to have the fans setup as yours is to try and overcome a lot of the issues with it all, apparently not ?? :D

when I helped firebug fit the VX wiring loom (L67) to his gemini I came up against these fan wires, I couldn't believe how bulky it all was for just fans!
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