95 Astro blowing HTR/AC 20A fuse

[c72lt1]

HTR/AC 20 fuse blows 2 to 3 minutes after AC is turned on. 130K miles. Replaced front AC Blower motor, did not help. Something drawing too much current but takes a little time to melt fuse. Any suggestions?

[c72lt1]

Either I am doing something wrong on the forum or no ideas? Anybody had any issues w/ the blower resistor pulling too much current? How about the AC compressor clutch coil pulling too much current?

[B.A.F.]

I just posted the same question. It wasnt my blower or my clutch. Did you find your problem yet?

[dewaynep]

I would say you are pulling too much current on the A/C compressor clutch. You should see if you can buy or borrow an inductive ammeter to see what the A/C clutch is pulling in amps. As an alternative you could disconnect the A/C clutch at the compressor and let the A/C run to see if the fuse blows, if it does not then you have found your problem.

[c72lt1]

Have not disconnected the clutch power yet to see if that is it. So still have not found the problem. Will try to work on it this weekend though. Last week end the '02 Astro decided to stop routing the AC air to the dash vents. It's the wife's car so I'll have to look at it first.

Any suggestions? Cooling air fine just not sending it to the dash. Seems to be damper control. Guess it's still pneumatic, maybe a vacuum line or busted actuator?

[Blue Bowtie]

Check the hard nylon vacuum line routed in front of the throttle body - They are prone to cracking and crumbling along the length:



There is also a a vacuum canister mounted low along the right subframe rail (below the arrow) which can suffer damage/leakage from shock and road debris.

[c72lt1]

Thanks a lot for the excellent info and picture. I'll check it as soon as the wife comes home. Once again really appreciate the help.

[c72lt1]

Thanks much. My wife thanks you also. It was separated about an inch from the manifold connection. Replaced the whole line w/ a rubber vacuum line. It was heat deteriorated like you said for 8" to 10", everywhere it was above the engine heat.

Shame Shame GM.

[c72lt1]

Forum,

Thanks for all the help. Found the problem on the 95 Astro. It was the wiring connecting to the Compressor clutch. The plastic tubing protecting the wiring had broken and the wire had rubbed long enough on the back edge of the compressor that it had rubbed away the insulation on the wire. Happened to be the positive wire not the ground. It was grounding to the compressor body and blowing the fuse. Wire chafing on a old car, something to check always.

Once again thanks much forum.