I've replaced the cooling fan and it's still not working. The owner before me had it straight wired on a switch but was removed before I bought it so I didn't think it was a issue being that I had the car for years without it running hot until about a month ago. What else could possibly be the reason it's not coming on when the car reaches the temp for it to do so because I want it to work properly with straight wiring it
Cooling fan not working
1 - 13 of 13 Posts
Joined
·
2,312 Posts
Usually a new member introduces themselves with a new member post.
Do you have a "tow package" car with one mechanical and one electric?
Or do you have a car older or newer than 94-96?
All the 94-96 Impalas have two electric fans. Most Caprice and Roadmasters did as well.
Do you have a "tow package" car with one mechanical and one electric?
Or do you have a car older or newer than 94-96?
assuming OP has a SS with dual EL fans...there was a TSB way back because the fan relays got so hot they melted the pin housing in the underhood fuse/relay box. Pull the relay and look. GM offered a outboard relay harness to fix this. Gary at Innovative Wiring makes a kit for both fans
Of course of wiring was butchered by PO to somehow bypass stock wiring, anything could be a shiat show fixing that
Of course of wiring was butchered by PO to somehow bypass stock wiring, anything could be a shiat show fixing that
Joined
·
2,312 Posts
OK you have two electric fans. Please give some details.
Are both not working?
Are one or two working when hot or when the A/C is turned on.
The usual first test is to unplug the temperature sensor on the water pump. The PCM will be forced to run both fans when you do this.
Rate yourself on car electrical knowledge. Zero is no understanding of circuit diagrams and no multimeter. Ten would be you have built a car from scratch.
Are both not working?
Are one or two working when hot or when the A/C is turned on.
The usual first test is to unplug the temperature sensor on the water pump. The PCM will be forced to run both fans when you do this.
Rate yourself on car electrical knowledge. Zero is no understanding of circuit diagrams and no multimeter. Ten would be you have built a car from scratch.
Tons of stuff on your car's symptoms in the archives, or just start scrolling through this section:
www.impalassforum.com
Heating/Cooling/HVAC
Heating and cooling and HVAC issues with the LT1 Reverse Flow Cooling System.
www.impalassforum.com
Joined
·
3,118 Posts
If it's an SS, it should have TWO radiator fans.
Now I REALLY don't trust your SS's previous owner.
You may not know that GM's original programs for LT1 cars have very high fan activation temp thresholds.
Simply put: GM programmed the fans to stay off until the engine gets pretty hot.
Previous owner did not reprogram the fan-on thresholds, instead he wired in his own solution, then modified that solution by removing the switch he used to turn on the fans when it got too hot for his tastes.
By how much am I off here?
Assuming two fans, and that you've already checked to see if either or both relays look melted ...
Did you check where the relays sit for evidence of burning / melting?
If the relays AND their seats look good, move to the next step.
Disconnect the H2Opump temp sensor, and describe what happens after you do.
Reconnect the H2Opump temp sensor after about 30secs.
If only one fan turns on, switch the fan relays seating positions.
Disconnect the H2Opump temp sensor, and describe what happens this time.
I'm about a 3 without a multimeter. The a/c fan works fine. It's the cooling fan that won't come on when the car heats up
They aren't cut. The previous owner tapped into the wire closes to the fan and straight wired it from there. I need it to work as it should. None of the relays are burnt and the fuses aren't blowed so I'm completely lost atp
You are pretty spot on. I have two fans. The a/c fan works fine. It's the cooling fan that's the problem. I've checked the relays. No signs of burning. I will check the pump sensor method when I get off work and lyk further details. I've checked all the wiring and everything is still connected properly. The previous owner never cut any wires. He just tapped into the hot wire on the fan and did his thing from there. The most logical solution you gave along with the others was the threshold programming. If that's the problem how do I reprogram it without taking it to a shop?
You are pretty spot on. I've checked the relays. No signs of burning. I've checked all the wiring and fuses. Nothing is blowed or cut. The previous owner just tapped into the power wire and did his thing from there. I will check the H20 sensor when I get off and give you a update. The most logical solution you gave alone with the others was the threshold programming. If that's the problem how do I reprogram it without going to the shop?
I have two fans also and the A/C fan works fine. It's the cooling fan that's the problem
I have two fans also. The A/C fan works fine. It's the cooling fan that's the problem
Joined
·
3,118 Posts
If you are concerned that the two radiator fans come on only when the engine gets pretty damn hot,
pcmperformance.com
because you have a '96 SS. (Were it a '94 or '95 I could help you myself.)
PCM Performance will, among many other much more fun things, lower the fan-on thresholds to much more reasonable temperatures. Just fill out the form.
pcmperformance.com
because you have a '96 SS. (Were it a '94 or '95 I could help you myself.)
PCM Performance will, among many other much more fun things, lower the fan-on thresholds to much more reasonable temperatures. Just fill out the form.
1 - 13 of 13 Posts
