A/C Experts needed
Thread Starter
Drifting
Joined: Mar 2004
Posts: 1,504
Likes: 0
From: Byron Center MI
A/C Experts needed
I have an 89 with C68. A week ago the wires for the coil of the AC clutch got caught on the pulley and tore off. When this happen it blew the 25a fuse for the AC. I have replaced the clutch and the clutch will not engage. Where do I go from here? The AC did work before this. Could the new coil be bad? Or did something else get damaged when this happen? Thanks in advance. Tim
Team Owner
Joined: Mar 2001
Posts: 54,124
Likes: 30
From: Cincinnati, Oh USA
When you turn on the a/c, the clutch should be activated. Measure if you have 12v across the clutch. If you do, the clutch should engage and the compressor should be turning. Pull the fuse and measure the resistance of the clutch coil, it will be very low resistance, several ohms.
Team Owner
Joined: Jan 2003
Posts: 20,254
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From: Summerland B.C. Canada
Drifting
Joined: Mar 2002
Posts: 1,251
Likes: 2
From: Thomson Georgia
You can see if any codes are set by pushing and holding them for about 5 seconds, the up/down fan speed buttons at the same time, then touch the auto fan switch to see the codes.
Then try to reset the AC control panel whether or not you have any codes. Seems like the top left fuse and the 2nd row 2nd fuse from the bottom. I think the method is the same for all electronic climate controls.
Just a thought
Johnny
Then try to reset the AC control panel whether or not you have any codes. Seems like the top left fuse and the 2nd row 2nd fuse from the bottom. I think the method is the same for all electronic climate controls.
Just a thought
Johnny
Le Mans Master
Joined: Dec 2000
Posts: 7,839
Likes: 22
From: San Diego, Ca
No a/c codes for the '89 to diagnose a clutch that won't engage. Also, are you sure the compressor didn't seize and that's how the wiring got caught up in the belt? Trust the shaft turns ok?
Power is from the a/c fuse to the coil - black/white wire - and back to the Blower Module - dark green wire - which provides the ground when a/c is requested. As JFB noted, there should be power across the connector with the ignition on. If not, the fuse is probably open or the wiring was damaged beyond the splice you made for the new connector. If you have power, ground the dark green wire. That should engage the clutch. If it does, and the clutch won't engage when a/c is requested, the module is bad and if it is bad, make sure the diode in the connector is good. (Note: I'm assuming that it all worked ok before this mishap - the assembly sends a low voltage signal to the module for a/c as long as the low pressure switch and high pressure switches are closed and there is a completed circuit to the ECM. If any of these other two circuits are open, it won't send the signal).
Power is from the a/c fuse to the coil - black/white wire - and back to the Blower Module - dark green wire - which provides the ground when a/c is requested. As JFB noted, there should be power across the connector with the ignition on. If not, the fuse is probably open or the wiring was damaged beyond the splice you made for the new connector. If you have power, ground the dark green wire. That should engage the clutch. If it does, and the clutch won't engage when a/c is requested, the module is bad and if it is bad, make sure the diode in the connector is good. (Note: I'm assuming that it all worked ok before this mishap - the assembly sends a low voltage signal to the module for a/c as long as the low pressure switch and high pressure switches are closed and there is a completed circuit to the ECM. If any of these other two circuits are open, it won't send the signal).
Le Mans Master
Joined: Dec 2000
Posts: 7,839
Likes: 22
From: San Diego, Ca
PS - If the Blower isn't working either, make sure there's power to the Module which is mounted on the Evaporator Case. It's the red wire and protected by a fusible link from the Battery, so there should be Battery Voltage on it at all times.
Thread Starter
Drifting
Joined: Mar 2004
Posts: 1,504
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From: Byron Center MI
JFB there is voltage at the clutch.
SunCr the compressor did not sieze the shaft spins freely. AC worked well before mishap. I had it in to have the car polished and asked them not to clean the engine compartment. Well they did and the best I can tell they power washed the engine and moved the wires closer to the clutch than it was. Also fuse blew when this happen. The fuse has been replaced and has voltage through it. I will ground the green wire and see what that does for me.
Agent 86 the PDF you posted will help. BTW if you are ever in West Michigan I owe you several beers for all the PDFs you have posted.
johnnyevans I have checked all the fuses in the fuse panel and all are good even the circuit breakers in the fuse panel.
Thanks for all the input and I will let you guys know what I find. I probably won't get to the AC until Sunday because I'm going to the Gratiot Cruise in Detroit on Saturday.
SunCr the compressor did not sieze the shaft spins freely. AC worked well before mishap. I had it in to have the car polished and asked them not to clean the engine compartment. Well they did and the best I can tell they power washed the engine and moved the wires closer to the clutch than it was. Also fuse blew when this happen. The fuse has been replaced and has voltage through it. I will ground the green wire and see what that does for me.
Agent 86 the PDF you posted will help. BTW if you are ever in West Michigan I owe you several beers for all the PDFs you have posted.
johnnyevans I have checked all the fuses in the fuse panel and all are good even the circuit breakers in the fuse panel.
Thanks for all the input and I will let you guys know what I find. I probably won't get to the AC until Sunday because I'm going to the Gratiot Cruise in Detroit on Saturday.
Thread Starter
Drifting
Joined: Mar 2004
Posts: 1,504
Likes: 0
From: Byron Center MI
Update. I grounded the dark green wire off the Blower Module and the compressor kicked on. So I will use the PDF that Agent86 posted to further confirm the bad module. Thanks for the help guys. Also anyone have any idea if the Blower Module is a dealer only part? Tim
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Le Mans Master
Joined: Dec 2000
Posts: 7,839
Likes: 22
From: San Diego, Ca
NAPA showed it in their online catalog the last time I looked - not that big of a price difference though. Module is the same for all Electronic Airs, so if you think the Dealer is giving you the "Corvette Tax", try Pontiac. Part # is available at www.acdelco.com