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cooling fan not working
- Zakarya Al-Yafei
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I have Tahoe 2010 LTZ cooling fan not working ( the car overheating )
temperature gauge working properly
I suspect in temperature sensor and I did replace it but nothing changed
I did diagnosed relay circuit for open or problem in relay and everything is working properly
when I bypass relay cooling fan working properly
what I found is there is no signal feeding cooling fan relay !
all fuse is OK
someone told me it need to online programming by GDI
is it ?
so how to do
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- cheryl hartkorn
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- Dylan
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what I found is there is no signal feeding cooling fan relay !
That's a problem sir

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- Tyler
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- Zakarya Al-Yafei
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I'm sorry for miss-info
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- Zakarya Al-Yafei
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I'm sorry for miss-info
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- Zakarya Al-Yafei
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Tahoe 2010 LTZ engine 6.0cheryl hartkorn wrote: what is an ltz? suburban? engine size so I can get a wiring diagram
I'm sorry for miss-info
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- Zakarya Al-Yafei
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I diagnosis fan LO and fan HI relaysTyler wrote: Could you be more specific about which cooling fan relay you're testing at? Here's the diagram:
It looks like the PCM controls the LOW relay to command both fans on at low speed, and controls the LOW and HIGH relays to get high speed. Are you seeing no power, or no ground at either relay?
and there was no power for both relay
through your diagram I recognize the problem is from the PWR TRN relay
can you tell (PWR TRN) is abbreviation for what ?
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- Tyler
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Nice catch on having no power at the fan relays! Let us know what you find at the PWR TRN relay, and we can go from there.
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