Cooling fan resistor - replacement tip
#1
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Cooling fan resistor - replacement tip
With the nose cover off the car, I crossed my fingers and checked out both ceramic resistors .... because only one spare sits on my tool bench: the oil cooler side was OK, but the AC ( left front) crumbled just by looking at it. To make it worse, the 10mm inner nut is seized - so that makes the idea of relocation more attractive .
The problem with relocation is that the wires are too short to reach a convenient spot .... so I took the plug & wires that fell out of the old unit and cut the plug off the spare: some soldering plus protective heat shrink tube applied doubled their length .... and allowed me to drill a mounting hole in the lower rear support bracket for the condenser. I swabbed the back side of the resistor with a dielectric paste ( to seal the porous ceramic and promote heat transfer). It was then a very easy replacement job.
So, if replacing a dead resistor, don't toss the old wires: reused, they may allow access to a better spot ....
The problem with relocation is that the wires are too short to reach a convenient spot .... so I took the plug & wires that fell out of the old unit and cut the plug off the spare: some soldering plus protective heat shrink tube applied doubled their length .... and allowed me to drill a mounting hole in the lower rear support bracket for the condenser. I swabbed the back side of the resistor with a dielectric paste ( to seal the porous ceramic and promote heat transfer). It was then a very easy replacement job.
So, if replacing a dead resistor, don't toss the old wires: reused, they may allow access to a better spot ....
#4
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#6
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Not really - they appear to be air ducts ( fresh air intake for the AC???), and they nose into the double walled, isolated section of the front inner fender liner.
I'll try to trace them when the car comes back, for I was curious too.
I'll try to trace them when the car comes back, for I was curious too.
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#8
Wallflower
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So the AC one is in the front... opposite the oil cooler one? My AC one was reported as bad in my PPI, but I rarely use the AC and haven't messed with it.
#10
As he said - they crumble. When I had my recent body work done, we replaced my AC one. It was literally falling to pieces. I really didn't know what it was, but got the number off either the resistor or PET and ordered a new one. I don't know that I could tell any difference in the functioning of the AC.
#13
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The AC one is bolted to the top of the "radiator" shroud located ahead of the LF wheel ( the beige coloured lump at top in the pic posted above - that view is from just in front of the wheel with the well liner removed). I found it far easier to ignore the stock location, and relocate a replacement as illustrated above - the big plus is that one could do that without removal of the bumper cover. Ditto for the oil cooler rad on the other side: its resistor is located on a "tray" sitting ahead of the rad that is almost inaccessible without removing the bumper; hgowever, by simply removing the RF fender liner, one can reach and unplug the wire harness ..... and relocate a replacement resistor to a new spot as for the AC side.
The resistor is a ~1/2" high ceramic disc of ~1.5" diameter - rated at a mere 0.45 ohms, but a whopping 55Watts: there was no sign of heat sink paste applied, so I'm guessing that they overheat, crack the ceramic and corrode the contacts & fail. The two speed fan then becomes single speed - but still works.
#15
Three Wheelin'
The resistor is a ~1/2" high ceramic disc of ~1.5" diameter - rated at a mere 0.45 ohms, but a whopping 55Watts: there was no sign of heat sink paste applied, so I'm guessing that they overheat, crack the ceramic and corrode the contacts & fail. The two speed fan then becomes single speed - but still works.
Are both resistors the same specification? Does anybody know who the OEM is? Are there any OEM part numbers on the unit? just curious...