01 Chevy Venture Cooling Fans & AC Not Working
December 27th, 2016, 12:38 PM
#1
CF Beginner
Thread Starter
Join Date: Dec 2016
Posts: 4
Likes: 0
Received 0 Likes
on
0 Posts
01 Chevy Venture Cooling Fans & AC Not Working
2001 Chevy Venture
Does anyone out there have any further insight on how to fix this ?
Problem: Cooling fans & AC compressor not turning when AC is on full blast, & there's no cold air. Though cooling fans do at least turn on and cool properly when temp gauge reaches normal range.
1. first noticed a problem when temp gauge was running higher than usual. Found that passenger side radiator fan was not turning on, even with AC cranked. Found there was 14 volts at the fan connector. I replaced the fan motor. The fans then worked and were running properly. They ran when the AC was turned on and when the temp gauge reached the normal range to cool the engine they turned on. So it looked like all was good. But I had noticed while replacing the fan motor that the 4 pin connector to the 2 fans was burned on the side of the fan which had failed.
3. After a few days of driving i then noticed the AC is not blowing cold. Fuses and relays all looked good. I noticed the ac compressor was not turning. There was very low voltage at the connector. (Though I could not properly seat the multimeter probes into the connector as they were too big, so I'm not 100% certain about the reading)
4. I also notice that the cooling fans are not turning on either when the AC is on. They were running with AC on after I had installed the fan motor, at least for some time. And again, they fortunately do turn on when the temp gauge reaches normal range.
I believe it could be a bad ground connection between the compressor and cooling fans. The AC button inside the vehicle normally powers up the cooling fans and angages the AC compressor clutch. Looking at a wiring diagram I have attached here both the cooling fans and ac compressor clutch both have a black wire with a connection that says "S105, ENGINE HARN 4CM FROM ENGINE FAN WIRING HARN BREAKOUT". I am assuming this has something to do with the connection that powers them both when you press the AC button. Apparently there is short in this connection it seems.
Also, an ongoing issue for a couple years which could be related has been with code P0128. What happens every few thousand miles is the check engine light will come on & at the same time the temp gauge stays flat, and the cooling fans will run continuously. I found that by either removing & replacing the fan relays, or by clearing the code, the problem temporarily resolves and all goes back to normal for a few thousand more miles.
Presently I have codes P0128 as well as
P0141 - (HO2S-12 Bank 1 sensor 2) / Heater circuit malfunction
P0440 - EVAP System No Flow During Purge
The P0141 and P0440 are codes which I've never had before, but they don't seem related to this issue. P0141 (O2 sensor related), P0440 (gas cap, fuel related)
Does anyone out there have any further insight on how to fix this ?
Problem: Cooling fans & AC compressor not turning when AC is on full blast, & there's no cold air. Though cooling fans do at least turn on and cool properly when temp gauge reaches normal range.
1. first noticed a problem when temp gauge was running higher than usual. Found that passenger side radiator fan was not turning on, even with AC cranked. Found there was 14 volts at the fan connector. I replaced the fan motor. The fans then worked and were running properly. They ran when the AC was turned on and when the temp gauge reached the normal range to cool the engine they turned on. So it looked like all was good. But I had noticed while replacing the fan motor that the 4 pin connector to the 2 fans was burned on the side of the fan which had failed.
3. After a few days of driving i then noticed the AC is not blowing cold. Fuses and relays all looked good. I noticed the ac compressor was not turning. There was very low voltage at the connector. (Though I could not properly seat the multimeter probes into the connector as they were too big, so I'm not 100% certain about the reading)
4. I also notice that the cooling fans are not turning on either when the AC is on. They were running with AC on after I had installed the fan motor, at least for some time. And again, they fortunately do turn on when the temp gauge reaches normal range.
I believe it could be a bad ground connection between the compressor and cooling fans. The AC button inside the vehicle normally powers up the cooling fans and angages the AC compressor clutch. Looking at a wiring diagram I have attached here both the cooling fans and ac compressor clutch both have a black wire with a connection that says "S105, ENGINE HARN 4CM FROM ENGINE FAN WIRING HARN BREAKOUT". I am assuming this has something to do with the connection that powers them both when you press the AC button. Apparently there is short in this connection it seems.
Also, an ongoing issue for a couple years which could be related has been with code P0128. What happens every few thousand miles is the check engine light will come on & at the same time the temp gauge stays flat, and the cooling fans will run continuously. I found that by either removing & replacing the fan relays, or by clearing the code, the problem temporarily resolves and all goes back to normal for a few thousand more miles.
Presently I have codes P0128 as well as
P0141 - (HO2S-12 Bank 1 sensor 2) / Heater circuit malfunction
P0440 - EVAP System No Flow During Purge
The P0141 and P0440 are codes which I've never had before, but they don't seem related to this issue. P0141 (O2 sensor related), P0440 (gas cap, fuel related)
Last edited by mikeshaw; December 27th, 2016 at 1:00 PM.
January 24th, 2017, 9:41 PM
#2
I had no cooling fans working even with AC. I spent hours testing electrical. As stupid as it sounds, it was the temp sending unit. It read the proper temps to temp gauge but for some reason disabled the fans. The wires to the sender are also thin garbage. Spent the $12 on the ECT and fans turn on. But only when the gauge gets 2 or 3 dashes past the center.
March 4th, 2017, 2:18 PM
#3
Did you fix this issue? The fans will not turn on with the A/C if the pressure is low. I recall testing the fans by either unplugging or jumping the 2 pins inside the temp sender connector. That worked for me. And like I mentioned before, although my temp sender was sending the correct temperature, somehow it was causing the fans to not operate. The fans typically do not turn on until the engine is around 230F. This is 2 or 3 marks over to the right from the center of the temp gauge.
June 27th, 2019, 1:47 PM
#4
CF Beginner
Thread Starter
Join Date: Dec 2016
Posts: 4
Likes: 0
Received 0 Likes
on
0 Posts
Sorry for the years later reply. But the reason why the compressor & fans weren't coming on is because the AC condenser had a leak and all the refrigerant escaped. There's a pressure switch which stops the compressor from running when refrigerant pressure becomes too low. The Chevy venture condenser has a bracket which is known to eventually crack and leak. I had it replaced and AC has worked fine ever since. However I've had an ongoing issue with the coolant fans failing. That thread is here:
https://chevroletforum.com/forum/ven...ed-wire-96127/
https://chevroletforum.com/forum/ven...ed-wire-96127/
