cooling fans not working 95 bonneville
#1
cooling fans not working 95 bonneville
A few days ago while i was driving, some genius decided that it would be a good idea to transport a dresser in the back of there truck with no sort of straps. So the top drawer flies out and smashes in my radiator and breaks both fans. I replaced the radiator and fans but the problem is that the fans arent spinning. I know that they both work because ive hooked them up directly to the battery. all fuses under the dash and hood are good and the high and low speed fan relays under the hood are fine as well. I'm not sure what else is involved in the system that could be wrong. Also, the relays are getting power but the main fuse under the hood is not. All help appreciated, thanks.
#3
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I don't have a diagram for a 95, but looking at a 98 the only things that can effect both fans is the fuse, or the ECT sensor providing the wrong temp to the PCM. Make sure the thermostat isn't stuck open causing to much cooling. The fans wont turn on until the temp gets to around 212* for fan 1 and 226* for fan 2
#4
Thanks for the quick response, i was wondering about the ECT.. Is that difficult to change? also how could the relays be hot if the fuse isn't? and if it was cooling too much it wouldn't be overheating tho would it?
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Depends on what post your checking. You need to look at the diagram and figure out what post is the switch. Then check for voltage threw that switch. There will be voltage to the relay no pater what as long as the fuse is good. But there are two relays, so I don't see that taking about both fans. Both relays get power from the same fuse. And both relays are controlled by the PCM.
#6
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I believe if you turn the air conditioning on, no matter what the coolant temperature, at least one fan will turn on high. Can someone with a '95 manual verify?
#7
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Both fans will turn on regardless of fan request.
Low speed fan will turn on at 212 F.
High speed fan will turn on at 226 F, or if the PCM see'* an open switch for the A/C refrigerant pressure fan switch indicating 210 psi or higher.
Here'* the schematic for the cooling fans as requested...
So, now first question is, what is leading you to believe the fans are not working?
Here is a quick and simple test to verify low speed.
Disconnect the electrical connector at the Engine Coolant Temp sensor located by the circle in this photo...then start the engine. The fans should turn on automatically. If they do not, then we need to troubleshoot deeper.
Low speed fan will turn on at 212 F.
High speed fan will turn on at 226 F, or if the PCM see'* an open switch for the A/C refrigerant pressure fan switch indicating 210 psi or higher.
Here'* the schematic for the cooling fans as requested...
So, now first question is, what is leading you to believe the fans are not working?
Here is a quick and simple test to verify low speed.
Disconnect the electrical connector at the Engine Coolant Temp sensor located by the circle in this photo...then start the engine. The fans should turn on automatically. If they do not, then we need to troubleshoot deeper.
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#8
mike thanks alot for the diagram and showing me where that sensor is. and no matter what i do, neither fan ever comes on but ill try to pull that plug and see what happens