I am have a problem with my fan motor not working on my 98 sunfire? What Do I need to know to fix this? I have replaced the motor, the relay and still have this problem? Or Is there way to bypass pass this on these cars so that when the car is run so will the fan?
do you mean the cooling fan?
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Get a jumper wire and run across the relay to make sure it kicks on.
Only other thing you'll get is a coolant temp sensor. The ECU reads the temp of the engine, and when it gets up around 210, it turns the fan on til it cools down to a predetermined point (maybe 10 degrees or so)
Sometimes it is the connector in the harness to the fan motor, I had the same problem and ater a new motor and relay it turned out that the connector was faulty.
Well I had to do the same thing that I did with my old sunbird. I wired in another relay into it so it turns on when the key is in the on postion. I will see if that Fix's my problem. Another Question tho is this suppost to do the same as the sunbird.
When The A/C buttons is Pushed or A/C is on. Does the Fan Cooling motor cut in?
I was told with the Older Sunbird that they do. But I failed to notice it if it did when it was working normally?
I have a OBD-II tool with my laptop and the coolin Temp seem working when I do the logging of the sensors.
Plus I have been getting a Error code of the Camshaft sensor, But I was looking around. And Came across some where that Said the CAM sensor will act up if the engine is overheating? The Error code # are P335 and P342.
Also check the grounds on the trans mount studs... mine wiggled loose = no fan
mine had the same problem ECT engine coolant temperature sensor was gone. try that prolly the problem.
Well my Didn't work so well.. Damn PCM pick up the other riged in relay and came up with the check engine light..
Damn Why can't the make these thing Easy to find the problems.. ;( I when for a drive today an there is no problems, Other then that 2nd O2 sensor drop to a error stat's on this test. Well I will have to run a thro the wiring and check the ground to see if it has come loose. I have also notice the Alt is only push out 13.5 Volts.
So where do you guys thing I should start if I don't have a ground problem?
PS.. Keep it Cheap tooo?
LOL..
The Orignal problem was it was starting to jerk on the highway, Change the Front O2 sensor, worked good for a few days then when all to hell again, So I bought a OBD-2 tester for my laptop to clear the codes plus see what Error codes it was pulling up. Found it has a miss fire reported in the test replaced plugs, wires and one of the dual coil packs, fuel filter. Problem is still there replaced air filter with a cloned K and N Air filtered box. Problem still is there I got those errors about the Camshaft Sensor. So I wired in the fan with the relay and then I got the Error code with the Relay problems removed my mod'd version. Change Fuel places and ran some full injection cleaners. Plus I have had some temp errors and Had my A/C refilled.
So Could A cooling sensor cause those types of problems?
Okay. So I can't find my hanes manual so I am doing these blind at this point.. Well With Help from this Site is pretty much all I have?
Read all before doing anything
Find the ECT sensor, it should be near the upper hose on the 2.2, 2 wires one yellow and one (black or brown), oval plug. Un plug that while the engine is running. This will force the pcm to send a command to turn the cooling fan on. It will turn the engine light on. If this turn on the fan then your fan circuit is fine, ie relay and motor, All that is needed is the ECT sensor changed. If it doesnt then you have either a wiring, ground or power issue. Only if the a/c compressor kicks on will you be able to see the cooling fan come on when a/c is turned on, either by the button or the selector switch. A/c will not operate correctly if the cooling fan doesnt come on, especially while ideling.
*****Im looking at a ground diagram, These items share the same ground (g114), cooling fan motor, electric brake control module, blower relay, post cat converter sensor(2nd o2), a/c compressor clutch, a/c compressor clutch diode. they all go to the ground on the left rear of the engine. (back bell housing bolt)
If you want to directly ground the cooling fan black/ white wire. this wire goes directly to the ground post. If you directly ground the blk of the a/c compressor clutch , this and all but the fan are spliced together in the harness and then go along the bottom of the radiator support. Its a possibility that you ran over something and broke the ground in the harness that runs under the radiator.
Your cam sensor wires are in that same harness, (brn/wht to pin c1- 7 to )(pink/blkpin 63 of c2)(red pin 36 of c2) c1 and c2 are the main PCM plugs.
There is a very good chance that your harness is smashed, I I rebuilt a wrecked J a few years back hit in the front for myself, 3 months afer, the car just quit on me on the high way a couple of times. I had it towed, started the car and started pulling on wires, I pulled on that harness and It would shut off. There were smashed wires, the insulation looked good but if you stretched the wire it would break. Caused by a pinhole in the insulation, water got in it and corroded the smashed copper causing a gap in the wire that was not visable from looking at it.
Since you are having several problems with circuits that go through the harness that goes under the radiator, that would be the first place I would look.
Let us know what happens.
01 cav w/01 3400 gam gt 4t45e
Hello Joe,
Okay I did what you said here is the problem. I pulled that ECT with the engine running and It did nothing. So I am looking for a ground problem, So where is the PCM in these Sunfire?
PCM in the 95-some '02 cars is located in the passenger fenderwell behind the bumper cover.
Where greg said it is. In front of the passenger side wheel, take out the front half of the fender liner splash shield to get to it easier. Your wiring harness starts there and attaches to the bottom of the radiator support. That is where I would suspect a broken wire. Make sure that the ground on the back bolt of the bell housing is tight too.
01 cav w/01 3400 gam gt 4t45e
Yea.. I realized that after I posted.. Dumb ass me.. Okay.. Well I Have rewire to the battery. With The TAN/White and the blk/white. No luck. get the ECT sensor to active when I removed the connection and make the fan kick in.
Off To Replace those Ground Wiring end and will see if that fix the problem?
But What else could be wrong with this? That would Cause this problem? And If I get needy and have to go to a junk Yard to pick up another PCM unit, Can I just Plug it in without doing anything else? Or are these PCM units more Testy then that. One With the same year and same model?
If you want to directly ground the cooling fan
black/ white wire. this wire goes directly to the ground post. If you directly ground the
blk of the a/c compressor clutch , this and all but the fan are spliced together in the harness and then go along the bottom of the radiator support. Its a possibility that you ran over something and broke the ground in the harness that runs under the radiator.
Where did you get a tan/ white wire from? Either ground the blk/wht wire on the fan or the black wire on the a/c compressor clutch.
Try to be a little more specific on what you have done when posting, Its hard to follow when it isnt a whole sentence.
I would pull the wire loom off of the pcm harness under the radiator and look for signs of smashed wires.
Its definetly a wiring problem because of the items effected are not related in any way but a wiring isssue. Especially since the a/c ,o2 sensor and cooling fan share the same ground.
01 cav w/01 3400 gam gt 4t45e
Okay.. I have come across a diode styled package on the A/C line. It looks to be spliced in to the 2 to cables is this normal? And Could this be my problem?
That sounds a bit fishy. Are you talking about the wiring to the pressure switch thats in the high-side line?
So The Tan white is connected to the Grd of the engine. I figure that it was a bad grd as well. Okay but I am wonder if it could be something relating to the PCM. I have notice the A/C Diode is okay. The Gnd to the AC is good! Tested with a ohm meter as well as run the voltage tester to the A/C and its getting a good grd from there. Another thing I notice when I remove that ECT sensor to test the fan to see if it comes on or I get an Error on the PCM but no errors or no fan when disconnected. I am know your right about the broken wire! But Which Wire is the problem? And How do I find it?
Okay, So here is what I have done so far
Tested the Ground connection on the front and side of the motor, Replaced the ends of the grounds.
Tested at Fan's Relay works Good. Works good there with a short the lead of the relay. I Also did a pigbacked relay to the radio. Which works to turn on fan but gave me a Check Engine say relay problems. Remove second relay.
Tested Relay from the A/C Clutch fan kicks in when short out bypassing the relay. A/C come on but Doesn't Active the Cooling FAN for the engine.
Removed the ECT sensor to see if fan enables but no fan or no Error code either when removed. Both when running and before starting.
Problem Is relating to a Heat problem.
Tested the Wiring Harness under the Rad. Removed Tape and inspected for breaks or holes nothing. Retaped.
Tested Diode to A/C no problems there.
There is an H20 in EVAP according to my laptops OBD-II scanner.
But no other problems reported by my Scanner.
It seem to have a surging when the Temp sensor surges.
But I am Suppect that this is a problem with my engine cooling motor not coming on when the A/C unit kicks in?
So Any Other Ideas or other spots to test?
Well I have tested the everything plus sent it into the dealer ship and Well I am Screawed.. It the PCM unit is buggered. So Anyone KNOW Where I can get one Cheap for this 98 Sunfire???? New would be nice but I am think it wouldn't be cheap? So I am going to See if there is one I can get around here? But I am think I am going to have a hard time.
I ran into a similar problem the other day, symtom was severe engine idle surge, no cooling fan when air was turned on. The high pressure switch in the a/c line had broken wires, all three, the wires were broken inside the insulation right as it goes in the plug. This sensor is mounted in the a/c line that goes under the upper radiator support, It will have 3 wires in a round plug. Pull on the wires to see if the insulation stretches. i found it by moving the wires around while the air and engine was on.
The original problem with the car was that a week ago he brought it in and said that the cooling fan wouldnt run and the air was not getting cold. at that time I put a cooling fan relay in it , recharged the a/c and sent it out. Seemed to work fine then, but it returned with the severe idle surge problem and no a/c.
If you end up getting a pcm find a used one and have it reflashed at a dealer to be sure that it has the correct programming in it. Unless yo are 100% sure of what it came out of, I wouldnt trust the Yards inventory records.
01 cav w/01 3400 gam gt 4t45e
