A/C compressor not kicking on. Any ideas?q

[CBZGT50]

A/C compressor not kicking on. Any ideas?

I have checked all the fuses and engine compartment relays, looked at the switch panel and everything looks perfect. I have recently rewired some of my gauges and my radio and since then it has not blown cold. The air blows, but I can see that the compressor is not kicking on. Any body with experience to get my A?C compressor gets a beer. ha ha. Seriously, I have a feeling it is in the dash but what component would cause the compressor to not kick on if all the fuses are fine?

 

[BlownFiveLiter]

I actually just fixed the same problem on my car, and it turned out to be the low pressure sensor on the accumulator. Replaced my old compressor this past Saturday due to that being bad, and letting the compressor run with no charge, and causing a nice fire on New Year's Day this year when I had the defog on. Charged it, and no go, so I pulled the harness off the sensor and put a jumper across to check if it ran, and it did. Check if you have enough refrigerant in your system, and if you do, try jumping it like I did, and see if it'll cycle on. The new sensor was $22 at the local NAPA here in town.

Matt

 

[CBZGT50]

I actually just fixed the same problem on my car, and it turned out to be the low pressure sensor on the accumulator. Replaced my old compressor this past Saturday due to that being bad, and letting the compressor run with no charge, and causing a nice fire on New Year's Day this year when I had the defog on. Charged it, and no go, so I pulled the harness off the sensor and put a jumper across to check if it ran, and it did. Check if you have enough refrigerant in your system, and if you do, try jumping it like I did, and see if it'll cycle on. The new sensor was $22 at the local NAPA here in town.

Matt

Can you give me a better description of the low pressure sensor? The car ran cold last wek until I did some rewire in the radio area. There are a plethora of wires and since I decreaced the rat nest, the compressor won't come on. I just pulled the bezel, the switch plate, and all the hoses and connectors seem just fine. I know th compressor is not bad and that it is not low on ref because it was ICE cold Six days ago. Five days ago, I rewired my stereo,/gauges to clean up the rats nest. Coincidence.

 

[BlownFiveLiter]

The low pressure sensor is right directly on top of the accumulator on the passenger side, right next to the firewall. To my knowledge, the sensors tend to go bad without warning, so it could be completely unrelated to the stereo and gauges. I'll see if I can get a pic of it for ya, and post it up here shortly, once my bro gets home and I can snag his digi cam.

Matt

 

[CBZGT50]

The low pressure sensor is right directly on top of the accumulator on the passenger side, right next to the firewall. To my knowledge, the sensors tend to go bad without warning, so it could be completely unrelated to the stereo and gauges. I'll see if I can get a pic of it for ya, and post it up here shortly, once my bro gets home and I can snag his digi cam.

Matt

I did recently change out the valve covers a little over a week ago. Maybe I unplugged it aciently or cracked it. Get a pic if you can. I think I know exactly where you are talking about. How did you check the sensor and determine it was bad, voltmeter?

 

[mo_dingo]

It's the black canister looking thing on the passenger side firewall.

If your compressor is not kicking on, here is where to start. Take off the plug on the compressor, and see if you have voltage. If yes, then your compressor clutch is bad. if no, move on to the accumulator.

See what happens when you remove the plug on the accumulator, and install a jumper wire on the plug. If the compressor kicks on, either the sensor is bad, or you have no refridgerant. Get a r-134a fill kit with a gauge, and see what the pressure is on the low pressure side (drivers side line). If you have enough pressure, then I would assume that the sensor on the accumulator is bad and replace it.
Scott

 

[1105]

switch is circled

 

[go-stang5.0]

WHat they said. When checking the switch just take a paper clip and bend it into U. Wnplug the harness from the switch and jump the harness. If the Compressor kicks on switch is bad. If not then thats not it. If it does kick on though dont leave it running like that cuz you will blow up the compressor. The switch is there so when the pressure gets high enough, the compressor shuts off to prevent over pressurizing . Thats why your compressor goes on and off when the ac is on and it does not just stay on all the time.

 

[CBZGT50]

You guys rock. I will try they stuff you said. I really have no experience with the Mustang A/C. I appreciate all the help. It's getting HOT here.