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Old 07-15-2017, 04:41 PM   #1
95gt302
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So my car has been overheating endlessly recently I replaced the t-stat then come to find out that the fan isn't turning on ive checked the fuse and finally caved and put in a new ccrm and still the fan doesn't come on my a/c also doesn't work id appreciate any help im sure there are plenty of threads on this already so feel free to attach them for now I just bought a new pigtail for the fan and have a switch wired in so I can drive the car but id like to turn on by itself and have a/c
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Old 07-16-2017, 06:19 PM   #2
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If the ac doesn't work, the engine will have to get up to 208 degrees to cut the fan on.

Before we get to tearing apart wiring, did the thermostat have a relief valve or did you drill a hole in it?
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Old 07-17-2017, 01:32 AM   #3
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Originally Posted by 95gt302 View Post
So my car has been overheating endlessly recently I replaced the t-stat then come to find out that the fan isn't turning on ive checked the fuse and finally caved and put in a new ccrm and still the fan doesn't come on my a/c also doesn't work id appreciate any help im sure there are plenty of threads on this already so feel free to attach them for now I just bought a new pigtail for the fan and have a switch wired in so I can drive the car but id like to turn on by itself and have a/c

Fan & AC are related. AC = ON, Fan MUST = ON. First order of the day. Run power directly to fan, see if it actually runs. If this is a 2-speed fan setup, check both speeds. AC may not be working because of no fan: excessively high refrigerant pressure = no AC. imp
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Old 07-17-2017, 01:32 PM   #4
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the thermostat came with a relief and I've run power directly to the fan and it does work I've also checked power at the harness and that has power as well the a/c compressor doesn't even try to cycle
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Old 07-17-2017, 01:47 PM   #5
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ive also replaced the coolant temp sensor
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Old 07-17-2017, 01:49 PM   #6
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the thermostat came with a relief and I've run power directly to the fan and it does work I've also checked power at the harness and that has power as well the a/c compressor doesn't even try to cycle
For the overheating, could be the coolant temp switch.
Have you hooked up manifold gauges to the A/C to check the charge? The lack of A/C could just be low on freon...which would mean a leak. The A/C command to switch the fan on would override the coolant temp switch.
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Old 07-17-2017, 03:44 PM   #7
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Hook the fan back up like it should be, pull the plug off of the Engine Coolant Temp sensor. Start the car,, the fan should kick on high. If it does, replace ECT check AC manifold pressure and operation of low pressure switch.

If the fan does not kick on high when you unplug the ECT, you could have a problem with the PCM ground that commands the fan to come on. Could be internal or it could be in the wiring leading up to the fan.
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Old 07-17-2017, 09:05 PM   #8
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the thermostat came with a relief \
i assume you did install the relief at 12 o'clock
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Old Yesterday, 02:07 PM   #9
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Hook the fan back up like it should be, pull the plug off of the Engine Coolant Temp sensor. Start the car,, the fan should kick on high. If it does, replace ECT check AC manifold pressure and operation of low pressure switch.

If the fan does not kick on high when you unplug the ECT, you could have a problem with the PCM ground that commands the fan to come on. Could be internal or it could be in the wiring leading up to the fan.
disconnect the PCM from the wire harness and turn the key on. If the fans come on, all the wiring, CCRM, and fans themself are good.
The PCM would also be good, as it commands the relays to OPEN, which turns the fans OFF.

Sounds more like a bad temp sensor to me. OP probably changed the wrong one.
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