AC problems
Senior User
Joined: Mar 2010
Posts: 241
Likes: 0
From: Independence, Ky
Hey pop, I did this to my truck this morning and everything seems to be working fine! One ? though. In one of you're replies you stated NOT to remove all the shims. Well mine only had the one shim that happened to be almost the exect amount I needed to remove. It leaves me with right around .020 air gap. Is that ok to not have a shim, or should romove it again and file down to almost nothing so as to leave something of a shim? Please advise Thanks for you're awesome info. Love this site, i dont think there's any problem that someone on this site can't help with! Let's face it ....as expensive as the sd's are to own, saving ANY amount on repairs is great! Thanks again!
Hotshot
Joined: Jan 2002
Posts: 17,988
Likes: 207
From: La La Land
It's perfectly OK to not have any shim at all, but you MUST have an air gap. If "no shim at all" gives you enough air gap, you're good-to-go.
If you'll tell me where I said not to remove all the shims, I'll go in and edit that to have a clearer meaning.
Pop
If you'll tell me where I said not to remove all the shims, I'll go in and edit that to have a clearer meaning.
Pop
Senior User
Joined: May 2008
Posts: 136
Likes: 2
From: the hood, Harrisburg PA
Awesome. I did this to my SD this morning. Worked like a charm. One tip I can give is that I didn't want to mess with jumpering the relay to lock the clutch so I just wedged a wrench against one of the three piers on the clutch plate, against the frame. Bolt turned right out with little effort.
Thanks SpringerPop!!
Thanks SpringerPop!!
New User
Joined: Feb 2011
Posts: 5
Likes: 0
Looked through this thread and found a lot of great information and things to check or test. Unfortunatly I have not found the solution for my A/C problem. Checked air gap... .030. Checked voltage at connector at compressor... NONE. Supplied voltage to compressor momentarily... CLUTCH ENGAGED. Checked for voltage at connector for cycling switch at acummulator... >11 v WHEN CAB CONTROL SWITCHED TO to AC or Max. Jumped cycling switch momntarily... NO VOLTAGE AT CLUTCH CONECTION.
Shop manual gives directions for testing both a high pessure cutoff switch and an AC clutch relay, but I have been unable to locate these so far. I havent purchased a wiring manual yet. putting some money aside for that and for repairing AC problem, when I find it.
Kevin
Shop manual gives directions for testing both a high pessure cutoff switch and an AC clutch relay, but I have been unable to locate these so far. I havent purchased a wiring manual yet. putting some money aside for that and for repairing AC problem, when I find it.
Kevin
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Senior User
Joined: May 2010
Posts: 396
Likes: 3
From: Los Angeles, CA
Looked through this thread and found a lot of great information and things to check or test. Unfortunatly I have not found the solution for my A/C problem. Checked air gap... .030. Checked voltage at connector at compressor... NONE. Supplied voltage to compressor momentarily... CLUTCH ENGAGED. Checked for voltage at connector for cycling switch at acummulator... >11 v WHEN CAB CONTROL SWITCHED TO to AC or Max. Jumped cycling switch momntarily... NO VOLTAGE AT CLUTCH CONECTION.
Shop manual gives directions for testing both a high pessure cutoff switch and an AC clutch relay, but I have been unable to locate these so far. I havent purchased a wiring manual yet. putting some money aside for that and for repairing AC problem, when I find it.
Kevin
Shop manual gives directions for testing both a high pessure cutoff switch and an AC clutch relay, but I have been unable to locate these so far. I havent purchased a wiring manual yet. putting some money aside for that and for repairing AC problem, when I find it.
Kevin
The instructions for testing the cutoff switch you already did. If the AC clutch relay wasn't working than you wouldn't be getting any voltage anywhere.
I put factory AC in my truck from scratch and found out that the only segment of additional wiring was a foot or so of harness. One end went to the clutch, the middle portion went to the cutoff switch and the other end went to an available connector on the passenger side fender.
Hotshot
Joined: Jan 2004
Posts: 19,760
Likes: 1,078
From: St Louis
On the '04 SuperDuty, the cycling switch does NOT directly control the AC clutch.
Instead, the series circuit of the cycling switch and the HPCO switch serve as an input to the PCM. Using a scan tool capable of reading Mode 6 data, you can view the state of this "AC Request" input.
The PCM, in turn and in accordance with its programming, will energize the AC Clutch relay. The relay, when energized, routes power from CJB F10 to the clutch coil.
The fuse is documented in your owner's manual, but it looks like the relay box is not. The relay is located in Aux Relay Box #4, under the hood, with the relays for the trailer turn signals.
Instead, the series circuit of the cycling switch and the HPCO switch serve as an input to the PCM. Using a scan tool capable of reading Mode 6 data, you can view the state of this "AC Request" input.
The PCM, in turn and in accordance with its programming, will energize the AC Clutch relay. The relay, when energized, routes power from CJB F10 to the clutch coil.
The fuse is documented in your owner's manual, but it looks like the relay box is not. The relay is located in Aux Relay Box #4, under the hood, with the relays for the trailer turn signals.
Hotshot
Joined: Jan 2002
Posts: 17,988
Likes: 207
From: La La Land
New User
Joined: Feb 2011
Posts: 5
Likes: 0
Thanks, I didn’t think it was that simple. Just seeing the difference in the gauge of wire used at the field coil and the cycling switch led me to believe there was a relay or two involved in this. The wiring diagram Pop supplied (THANKS) shows the AC relay in aux box # 5 for diesels, which is what I have.
The shop manual starts out with instructions to check the command from the PCM. Unfortunately I don’t have the tool needed for this. I was trying to see if there was a wiring, fuse, or relay problem I could fix before I pay someone to work on my truck. I had already checked fuse #10 in the CJB. I think I’ll see if I can locate Aux. Relay Box #5 and do some checking there.
Thanks
Kevin
The shop manual starts out with instructions to check the command from the PCM. Unfortunately I don’t have the tool needed for this. I was trying to see if there was a wiring, fuse, or relay problem I could fix before I pay someone to work on my truck. I had already checked fuse #10 in the CJB. I think I’ll see if I can locate Aux. Relay Box #5 and do some checking there.
Thanks
Kevin