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| Fan doesn't come on | |
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| Tweet Topic Started: May 5 2013, 11:28 AM (815 Views) | |
| Broke44 | May 5 2013, 11:28 AM Post #1 |
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New Member
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Hello all. I finally have a problem that doesn't have a hundred old posts about it. I have 96 1.0 manual. We rebuilt my engine and when putting it back together realized that the coolant temp sensor was damaged. When we finally got everything running properly the fan was running continuously like the sensor had an open (fan would start as soon as the key was turned on). So I thought, simple fix right? I got the new sensor(the 3 pin kind) and put it in and now the fan doesn't come on at all. Temp gauge works, cold idle advance seems to work but no fan. I had the sensor kicking around in my pocket most of the day, so I don't know how easy to break they are. Sooooooo I have another sensor coming. Everything worked great before, so I'm sure it has to be the sensor. My Chilton manual says that for the 96 and up cars, if the fan doesn't come on at 205F, it could be the PCM. Could I have screwed something else up? Does anybody have any other suggestions? |
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| Memphis metro | May 5 2013, 11:57 AM Post #2 |
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Check all fuses for a popped fuse as well as your intake grounds. Make sure you did not leave any disconnected. Check your black/blue wire going into your radiator fan relay with a test light and see if it has voltage. If not check for blown 30 amp radiator fuse or break in the black/blue wire. Check for voltage on the black/white wire going into the relay. No voltage present check for blown 15amp IG fuse. If voltage is present then ground the blue wire into the relay and see if the fan operates. If fan operates then supply battery voltage to blue/red wire at fan. If fan does not operate, ground black wire and see if fan works. If fan works check ground connection. Ground connection good suspect coolant sensor or pcm issues. |
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| mrchance | May 5 2013, 01:04 PM Post #3 |
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Blucifer's owner - Brad
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i agree with BR... stop throwing parts at it till you know what is broken. Test, assess, replace. You will have more success this way. also, you say the temp gauge works... do you mean it is going up/down as the car heats up/cools? Is your upper Rad hose getting warm consistently with the gauge in-dash? Edited by mrchance, May 5 2013, 01:11 PM.
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| Broke44 | May 5 2013, 04:17 PM Post #4 |
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Thanks for the response guys. Temp gauge works as the car warms up. both radiator hoses are hot as the gauge gets higher. When I disconnect the temp sensor the dash gauge quits working and the fan automatically comes on. So I assumed all the fuses and relays were good to the fan. It's just not coming on when it gets to the right temp. I checked grounds and they were all hooked up and tight. But I'll go check fuses and power to and through fan relay. Thanks |
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| Old Man | May 5 2013, 04:33 PM Post #5 |
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check your grounds too |
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| 1DCGUY | May 5 2013, 05:25 PM Post #6 |
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Don't be a "Richard"
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How long are you letting the car run before your deciding that the fan isn't running like it's supposed to be? These motors take a loooong time to get the temp up before the fan kicks in. I've had to let a few of them run for over a half hour to get the fan to kick in. Be patient if the gauge is working. |
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| Memphis metro | May 5 2013, 06:14 PM Post #7 |
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Just curious, did you put a new thermostat in the car while you were working on it? |
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| Broke44 | May 5 2013, 09:02 PM Post #8 |
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OK got a question.
Big Rhino I have to do this with relay in right? How? I get voltage at both places to the relay. And I can run 12v and ground to the fan and it works great.
I'm letting it run until the temp gauge needle is almost in the red(1/8 inch away), and the radiator hoses are almost too hot to hold onto.
No I didn't change it. I ran a manual toggle switch to the fan for now. At least till I get another sensor. Does anybody know if or what the ohms readings should be across the 3 pins in the temp sensor hookup? Thanks for the help guys |
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| Memphis metro | May 5 2013, 09:45 PM Post #9 |
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You can run a short wire from the battery negative terminal to the blu into the relay. We had a situation here while back about the 96 sensors as to gauge control and fan control. Stiffcheese would be a good person to ask about the sensor, he has a 96 FSM. There are slight variations on gauge senders and temp sensors from year to year. Was the original sensor a 3 pin sensor? |
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| Broke44 | May 5 2013, 10:41 PM Post #10 |
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Yes the original was a 3 pin sensor. I was hoping it was a 2 pin, cause I've got 2 of them in the garage lol. |
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| Broke44 | May 6 2013, 11:19 PM Post #11 |
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Well it seems I have bigger problems than the fan not coming on. I drove the car to work today with a manual switch to turn the fan on if it got hot. It started to get hot, so I turned the fan on. It kept getting hotter! Finally turned the defrost on high and limped it to work. So I'm pulling the radiator out tomorrow to take to get tested, and I think I'll replace the thermostat as well. My radiator guy says it could be either. So we'll see. |
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| Broke44 | May 15 2013, 10:45 PM Post #12 |
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WooHooooo!!! I finally got it fixed! Radiator was plugged almost solid (radiator guy couldn't believe I made it out of town without frying the motor), so I replaced it. Thermostat had some silicone stuck in it so I replaced it with a new one (192 F). And I replaced the coolant temp sensor with another new one from rock auto. Car doesn't overheat and the fan comes on when it's supposed to. Not sure why the other new sensor didn't work. Ohms readings looked pretty close on both of them cold. Didn't really check when it was warm. The sensor that didn't work was Import Direct from O'reilly's if anybody was curious. Anyway, really happy to have my baby back on the road.
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I finally got it fixed! Radiator was plugged almost solid (radiator guy couldn't believe I made it out of town without frying the motor), so I replaced it. Thermostat had some silicone stuck in it so I replaced it with a new one (192 F). And I replaced the coolant temp sensor with another new one from rock auto. Car doesn't overheat and the fan comes on when it's supposed to. Not sure why the other new sensor didn't work. Ohms readings looked pretty close on both of them cold. Didn't really check when it was warm.
7:22 PM Jul 10