Cooling Fans don't work
09-17-2006, 04:40 PM
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Cooling Fans don't work
I am currently tracking down a DTC 26 and I think it has to do with my non-working cooling fans. No fans when the A/C is turned on and no fans when terminals A and B of the ALDL are shorted, so I'm pretty sure they don't work. All three relays on the driver side fender all click, though I guess they could a bad connection internally. My SES light will come on around 40mph and will always shut off if I turn the A/C on, which from my scan forces a fan #1 request, probably tricking it into the fan being on. Where should I look to remedy this problem?
09-17-2006, 04:51 PM
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The bigger driver'* side fan will work when hooking 12v+ straight to it. The smaller fan looks more difficult to test, but I'll try it in a bit. All three relays have constant 12V+ going to them as well.
09-17-2006, 05:07 PM
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Hi/low of the large fan and the small fan all work when looked up manually. All three relays click when manually hooked up. When shorting A and B of the ALDL, I can hear the EGR click, canister purge click, IAC clicking, but nothing from any fan relay. Are all fans controlled by the ECM or does one or the other have a temp switch somewhere?
09-17-2006, 05:22 PM
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PCM/ECM monitors coolant temperature & vehicle speed sensor to determine when to turn on the fans. As you discovered the AC will also turn them on. I'll post a wiring diagram ASAP.
09-17-2006, 06:27 PM
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Bah, the problem was extremely over thought, I blame the SES light though. Cooling fan fuse was missing. I've owned the car for three years and it was there at one point, I did just get the car back from being borrowed from my sister, but I doubt she knows what a fuse is let alone mess with it. Either way, fans now work and DTC 26 is gone. Thanks for the help guys!
09-18-2006, 10:25 PM
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And here I was about to chime in on my troubles with my coolant fans.. lol.. I spent 8 months of swearing and troubleshooting (usually one and the same.. 
)
Glad to hear that you got them working, as I know it can be rather stressfull driving in traffic, watching the temp going up, and trying to figure out where you can get out and run the car fast enough to cool her...
) Glad to hear that you got them working, as I know it can be rather stressfull driving in traffic, watching the temp going up, and trying to figure out where you can get out and run the car fast enough to cool her...
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