New motor is and now the fan won't stop???
11-14-2005, 08:11 PM
#1
Instructor
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New motor is and now the fan won't stop???
I just installed a new 383 in my 89 and fired it up for the first time.
the problem is my main fan runs all the the time.I did delete the AC
and I am wondering if it may be related.It has a Miniram so the EGR was also deleted.Any input would be appreciated.
the problem is my main fan runs all the the time.I did delete the AC
and I am wondering if it may be related.It has a Miniram so the EGR was also deleted.Any input would be appreciated.
11-14-2005, 10:54 PM
#2
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There is a pressure sensor on the a/c plumbing on the right side of the engine that controls the fan. If it is disconnected, the fan stays on. Hopefully someone will have more sprecific information.
11-15-2005, 12:07 PM
#3
Le Mans Master
Per above - a/c fan switch mounted on the high pressure line gets ignition voltage from the ECM and grounds it when the switch contacts are closed. The ECM sees 0 volts and keeps the fan off. When the switch opens, such as when you disconnect it, the ECM sees voltage and grounds the main fan relay. So, you need to find a path to ground for this signal. It's from PIN D11 - I'd jumper it to the frame.
PS: There's another member who could use that switch - if you want to get rid of it, send me an email or IM.
PS: There's another member who could use that switch - if you want to get rid of it, send me an email or IM.
11-15-2005, 05:51 PM
#4
Drifting
Which switch is it? There are 3 switches on the ac lines. One has a large connector and is about an inch away from the evaporator, the other two, one with a large and one with a small connector are down on the lower line.
Each has a black wire, which I assume is ground, and a color wire. I tried jumpering each to ground, and the fan stayed on. I'm in the same boat as 89corvetteken. I just deleted my ac system and the fan stays on whenever the motor's running.
Chris
Each has a black wire, which I assume is ground, and a color wire. I tried jumpering each to ground, and the fan stayed on. I'm in the same boat as 89corvetteken. I just deleted my ac system and the fan stays on whenever the motor's running.
Chris
11-15-2005, 06:36 PM
#5
Le Mans Master
The switch closest to the Evaporator on the larger, upper line, is the Low Pressure Switch. Fan and the High Pressure Switch are mounted on the smaller, lower line, next to each other. Input to the Fan Switch from the ECM (at least for the '89) is Dark Green. Input to the High Pressure Switch is Light Green. Jumper Dark Green to ground and the fan should turn off. If you jumper the ground side or black, fan is going to continue to run because it needs the contacts in the fan switch to be closed to complete the path to ground.
11-15-2005, 06:36 PM
#6
Drifting
Nevermind, I figured it out. I checked the pinout in the shop manual.
The switch to go for is the small one located down low. It'll have a dark green and a black wire.
If you jump the two, it's the same as the switch grounding the signal and the fan will act like the ac is hooked up and turned off.
Chris
The switch to go for is the small one located down low. It'll have a dark green and a black wire.
If you jump the two, it's the same as the switch grounding the signal and the fan will act like the ac is hooked up and turned off.
Chris