Neon AC woes

My compresser isn't coming on in my 2000 neon. I had 1.56lbs of r134a in it which I topped up. Put leak dye in it and some oil. I've checked all the usual culprits and finally found it to be an electrical problem. We did this by jumping the compressor with 12v and it clicked on right away. Ice cold air coming out.

So, does anyone have a hint as to where to start checking first? Or better yet, does anyone have the ability to scan in a wiring diagram for the AC system and send it to me? I'd be forever in your debt!

Mike

Reply to
Mikhael47
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You started with 1.56 pounds and added from there? Or you added 1.56 pounds to whatever was in there already? What does the dataplate say is the correct fill amount? And how much is "some oil"?

That doesn't necessarily mean you have an electrical problem per se. Remember, the system has LPCO and HPCO switches (Low Pressure and High Pressure Cut Out) that will prevent the compressor coming on if the system charge is too low or too high. What do your low and high side pressures look like when you jumper the compressor?

Reply to
Daniel J. Stern

Sorry, it had 1.56 lbs recovered, then I filled it to the spec if 1.875lbs. I recovered several ounces of oil (not sure exactly how much because the machine's oil recovery tank was bubbling) and put in 4oz. I also put in approx 2oz of dyed oil.

I don't remember what the pressure said however the mechanic that hooked up the machine said it was within normal range and he said (as soon as he hooked up the machine) that the pressure was good enough for the compresser to engage.

I can take the car back in and check the pressures on both the hi and low side. What should that car have as optimal pressure?

Mike

Reply to
Mikhael47

Check the pressure switch. If pressure is too high or too low the compressor will not run. If the switch is bad it will not run. Running with pressure too high OR too low can cause serious damage.

Reply to
nospam.clare.nce

It might be the pressure sensor, however I am not sure. It seems to be the sensor that is right on the compressor. There is one on the 'front' and one on the 'side'. The one on the front is the one that doesn't seem to be doing anything. It's a black plug with several wires coming out of it. The one on the side of the compressor is white, different connector. Does anyone have a wiring diagram to explain what these 'sensors' do and where they are all located?

Correct me if I am wrong but I am assuming the pressure sensor on the aluminum block at the firewall is the pressure sensor. It seems to work as usual. If I unplug it, the fan goes off and the engine rpms lower. The one on the side of the compressor acts the same way. The one on the front of the compressor does not do anything when disconnected.

When I put a light on the fuse for the AC, it does not light up. The fuse appears to be good, I did not swap it yet. There is also a relay, I did swap it with no difference.

If I jump the sensor on the compressor itself, the compressor engages.

It's got to be a sensor or short in a wire as the pressure in the system is good, and there doesn't seem to be any leaks the needles on the guages stay put and don't fluctuate at all. When I did the recovery, the system gets purged by creating a vacum. The guages stay solid at the maximum negative pressure. If it were leaking I should see the pressures vary while purging. There is no dye coming out anywhere.

When the machine is hooked up the pressures are normal and steady. I did not check to see if anything changes when the compressor is jumped (engaged).

Thanks for your time

Mike

Reply to
Mikhael47

Rather than be in anyone's debt, why not simply spring for the $25 for a years subscription for the downloadable info. from

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Along with the factory schematics right out of the FSM (IOW, the real schematics specific to your vehicle), plus full TSB's also specific to your vehicle? Surely the FSM info., not to mention the TSB's, would be worth that much to you over a year's time if you do your own work, as you apparently do (and I'll quit calling you "Shirley"). (BTW, second year renewal and/or a subscription for any additional vehicles will be only $15 per vehicle per year.)

Bill Putney (to reply by e-mail, replace the last letter of the alphabet in my address with "x")

Reply to
Bill Putney

That's a pretty good idea.. I'll check into it. I'd of bought a manual already but in my area they are hard to come by for that generation of neon.

Mike

Reply to
Mikhael47

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