AC compressor wire thingy

[RLDSL]

The power to my AC compressor clutch quit, and I chased it down to a thingy in the wire going to the clutch, about 6" back from the plug. It looks a bit like the usual furd fuseable links, but it was marked as a diode and a 27 ohm resistor.

I called the dealership and their parts guy said , they don't have them and can't get them anymore. He let me talk to the service guy and he said to just cut it out and put some wire in there, which I'm inclined to agree with since I've never seen anything like that in the power line going to an ac clutch before.

IT that thing in there for some magic reason, or is it just another one of those better ideas that ford shouldn't have had.

Thanks--------Robert

 

[sassyrel]

go to radio shack with that diode--and replace it--or you may find residual back current not letting the truck shut off--they arent expensive---

 

[7.3shrk]

are you sure its that thing, and not the pressure switch?

 

[RedTruck]

If the combination is in series I'm guessing it's a regular (probably silicon) diode. I would venture to guess that you would be able to replace it with the same diode used in the High Idle Solenoid Mod in the tech articles. If you can read the number on it you may be able to find a replacement at Digikey.

The reason for this circuit is probably to protect your truck wiring or your AC clutch from the inrush caused by the clutch electric solenoid coil. You can bypass it and it will probably work for a while, but I'm guessing you'll have problems down the road.

Also, if this combination failed it is likely that this is the result of some other problem.

 

[ramon f350]

I would try the pressure swith first to make sure they are like 9.00 if i remeber right.

Ramon

 

[RLDSL]

are you sure its that thing, and not the pressure switch?

No, pressure switch was fine, current stopped at the diode/resistor piece. I cut it out and put a couple of pieces of wire in and it's good to go.

I guess I'll leave it like that for now, if it gives me any trouble shutting off, I'll just pull the wire on the pump and deal with the diode then.

--------Robert

 

[Gary79F250]

I would replace the diode, The reason that it is in there is to prevent a back voltage spike from the field collapse as the clutch cycles in and out. It will spike higher than 12 volts. If you have anything computer controled it could in theory cause harm. As for the truck not shutting off, I wouldnt wory about it. if you dsecide not to replace it.

 

[RLDSL]

If the combination is in series I'm guessing it's a regular (probably silicon) diode. I would venture to guess that you would be able to replace it with the same diode used in the High Idle Solenoid Mod in the tech articles. If you can read the number on it you may be able to find a replacement at Digikey.

The reason for this circuit is probably to protect your truck wiring or your AC clutch from the inrush caused by the clutch electric solenoid coil. You can bypass it and it will probably work for a while, but I'm guessing you'll have problems down the road.

Also, if this combination failed it is likely that this is the result of some other problem.

I imagine the reason it failed is a quarter million miles in a hot climate. Most of the wires in that vacinity, I've had to replace from dried out brittle insulation. Either that or the old compressor that i just replaced was putting too much load on it..

-------Robert

 

[RLDSL]

I would replace the diode, The reason that it is in there is to prevent a back voltage spike from the field collapse as the clutch cycles in and out. It will spike higher than 12 volts. If you have anything computer controled it could in theory cause harm. As for the truck not shutting off, I wouldnt wory about it. if you dsecide not to replace it.

Manual trans, I don't think there's any high tech in this beast

 

[Agnem]

I would replace the diode, The reason that it is in there is to prevent a back voltage spike from the field collapse as the clutch cycles in and out. It will spike higher than 12 volts. If you have anything computer controled it could in theory cause harm. As for the truck not shutting off, I wouldnt wory about it. if you dsecide not to replace it.

He is 100% correct. Your radio and gauges may suffer depending on the voltage. At a minimum, it will burn out the contacts on the relay or switch that controls the clutch.