A/C Fuse Blowing
09-05-2004, 03:46 PM
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A/C Fuse Blowing
I have an 87 944 Turbo that keeps blowing the 7.5 Amp fuse. I haven't found an electrical diagram that shows me what that fuse is connected to. When it blows the compressor stops compressing and the light on the HVAC control go out. The fans still blow air but the recirc, defrost and A/C lights no longer work and the defrost doesn't turn on the compressor or run the fans at full speed like normally.
It appears to me to be either the compressor or the control box (I am hoping the control box $$). Does anyone know which might exhibit these symptoms or if something else might be the cause?
It appears to me to be either the compressor or the control box (I am hoping the control box $$). Does anyone know which might exhibit these symptoms or if something else might be the cause?
Last edited by gkinder951; 09-05-2004 at 04:22 PM. Reason: Wanted to add avatar
09-07-2004, 06:13 PM
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Three Wheelin'
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I was told that as the wires age, they become poorer conductors and more current needs to be drawn which can blow a fuse. In my case, the mechanic put a slightly larger fuse (like a 30 amp fuse instead of 25) and since then no more blown fuses. But don't use a significantly higher rated fuse because the fuses are there for safety.
09-08-2004, 05:34 PM
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Heh, I had the fuel pump fuse blow over and over for about 4 hours one day. Puzzled the living @#*$ out of me, probably went through 20 fuses...then it just stopped...weird bugs.
09-08-2004, 06:40 PM
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Burning Brakes
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I have seen several clutches fail, disconnect the wire to the clutch and try it, see if it still blows the fuse. The power wire to the clutch is just inside the left frame rail, near the sway bar bracket and the ac hose, it is a single wire and had a clear plastic insulator around the connection.
09-09-2004, 01:45 PM
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I'll try disconnecting the clutch. I went to a 10 amp fuse and it worked for about a day. Then it blew. I replaced the 10 Amp fuse and now they just blow right away. I am a little worried about doubling the fuse rating to 15 A (not sure how much the wiring can take).
From reading up on it, it sounds like the clutch magnets are not part of that fuse circuitry and that the clutch magnets need about 25 Amp (I assume that this is the 25 relay), but it's worth a try to disconnect it and see for sure. I could probably just pull that relay to see.
Right now I am inclined to think HVAC control box.
From reading up on it, it sounds like the clutch magnets are not part of that fuse circuitry and that the clutch magnets need about 25 Amp (I assume that this is the 25 relay), but it's worth a try to disconnect it and see for sure. I could probably just pull that relay to see.
Right now I am inclined to think HVAC control box.
