having a problem with my primary fan coming on...help me
11-11-2007, 05:32 PM
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Car: 90 Formula, 02 ws6
Engine: 305 tpi, ls1
Transmission: 700r4, t-56
Axle/Gears: stock posi 2.73, 12 bolt with 4.11s
having a problem with my primary fan coming on...help me
well heres the deal
when the car gets up to temp for the ecm to turn the main fan on it does not
the relay is good and when i jump it out manually the fan kicks on so i know i have power and the fan works
when i put on the ac the fan comes on just fine so i know the ecm is telling it to turn on so the wire going to the computer is good. the secondary fan does not come on(because theres not enough pressure in the ac system though)
i changed the coolant temp sensor thinking that it was bad and thats why the fan was not working...not the case. i have 5 volts coming from the ecm on the yellow leg and i tested the contiuity of the black ground wire and that tested fine as well so im at a loss on what the hell is wrong
anyone got some input...
thanks
joe
when the car gets up to temp for the ecm to turn the main fan on it does not
the relay is good and when i jump it out manually the fan kicks on so i know i have power and the fan works
when i put on the ac the fan comes on just fine so i know the ecm is telling it to turn on so the wire going to the computer is good. the secondary fan does not come on(because theres not enough pressure in the ac system though)
i changed the coolant temp sensor thinking that it was bad and thats why the fan was not working...not the case. i have 5 volts coming from the ecm on the yellow leg and i tested the contiuity of the black ground wire and that tested fine as well so im at a loss on what the hell is wrong
anyone got some input...
thanks
joe
11-11-2007, 07:35 PM
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Car: 81z-28,89gta,91z-28 03 1500
Engine: 355,L98vette tpi,327
Transmission: TH350/700R4/700r4/4l80E
Axle/Gears: 3;73/3;27/2;73/3;73
Re: having a problem with my primary fan coming on...help me
might be the switch on the passenger side head.It has a similar connecter to the knock sensor.It is located just under the spark plugs 6&8 cylinders
11-12-2007, 12:37 PM
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Car: '91 Z28 convertible
Engine: TPI
Transmission: T5
Axle/Gears: 3.27 posi disc
Re: having a problem with my primary fan coming on...help me
Guys, he's talking about the PRIMARY fan, so the backup switch in the passenger head is out of the question here.
Joe, do you have access to a scanner for your car? A friend with a scanner maybe? That would tell you whether the ECM sees the right temperature of the engine and also whether it tries to turn the primary fan on.
How hot did you let it get? The primary fan kicks in WAY past 220 (at least on my car). Just checking to be sure.
You can, if you want, turn on the ignition and ground the green/white wire on the coolant fan relay. That will tell you two things: the relay works ok and you got the right fan.
You can also drop the passenger side kick panel and pull the ECM down from the dash. Then locate and disconnect the C2 connector (it's the big black one) and measure resistance between D2 and C10 pins (on the harness side). You should see resistance corresponding to the engine temp (from this table). That will tell you whether your ECM sees the CTS signal correctly.
Hope this helps.
Lou
Joe, do you have access to a scanner for your car? A friend with a scanner maybe? That would tell you whether the ECM sees the right temperature of the engine and also whether it tries to turn the primary fan on.
How hot did you let it get? The primary fan kicks in WAY past 220 (at least on my car). Just checking to be sure.
You can, if you want, turn on the ignition and ground the green/white wire on the coolant fan relay. That will tell you two things: the relay works ok and you got the right fan.
You can also drop the passenger side kick panel and pull the ECM down from the dash. Then locate and disconnect the C2 connector (it's the big black one) and measure resistance between D2 and C10 pins (on the harness side). You should see resistance corresponding to the engine temp (from this table). That will tell you whether your ECM sees the CTS signal correctly.
Hope this helps.
Lou
11-12-2007, 08:59 PM
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Car: 90 Formula, 02 ws6
Engine: 305 tpi, ls1
Transmission: 700r4, t-56
Axle/Gears: stock posi 2.73, 12 bolt with 4.11s
Re: having a problem with my primary fan coming on...help me
well i checked everything out and let it heat up to past 220 and the fans finaly cam on at 230 and off at 220
i have not had a stock thirdgen in 8 years haha i forgot it was set to go on that high
i will probably get a 180 stat and a fan switch for the secondary fan that turns on around 200 and off at 180 or so making the secondary fan my primary one
sounds like a plan to me
i have not had a stock thirdgen in 8 years haha i forgot it was set to go on that high
i will probably get a 180 stat and a fan switch for the secondary fan that turns on around 200 and off at 180 or so making the secondary fan my primary one
sounds like a plan to me
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