No cold air

Sorry for letting you sit. My Verizon e-mail is going through major changes, (none of them for the better), and sometimes it goes down for an entire day, then I don't get the automated messages directing me to your reply.

How are you jumping the compressor to make it run? Do you just need the posiitve wire, or do you have to connect a ground wire too?

The most accurate way to measure the voltage on the clutch coil is with it plugged in. When it should be turning on, measure the voltage between ground and the 12 volt wire, then between ground and the ground wire in the plug. If you have 12 volts on the ground wire, that ground wire is the circuit that needs to be looked at.

Caradiodoc

Hi Runnikee. I think your last comment might be the key. You should never HAVE to use a c-clamp to push the pistons in. If a ring of dirt or rust has built up around the pistons, they wil stick on the seals and won't release properly.

Try stopping on a slight incline to see if the car will creep ahead on its own in neutral when you release the brake. If it does not, crack open the steel lines at the master cylinder and see if they release. (You might want to put a block of wood in front of one tire so you don't look funny chasing your car down the hill, like happened to me once). If that doesn't help, try opening the bleeder screws on the calipers. (No block of wood needed. The car will stop when it tries to run you over! :)). If that doesn't help, the calipers will have to be replaced or rebuilt. In the '80s, we rebuilt calipers with every brake job, but today professionally rebuilt calipers with a warranty are so inexpensive, it doesn't pay to do it yourself unless you're "emotionally involved" with them and want to keep the original parts.

The calipers are most suspect since the problem started when the pistons were pressed in to make room for the new, thicker pads. If, however, you had to replace the pads because the brakes were staying applied, cracking open the hydraulic system at the master cylinder or bleeder screws will point towards a constricted hose, (unlikely to have two at once), or brake fluid contamination.

Caradiodoc

I like to pry the pistons in with a flat blade screwdriver before I unbolt the calipers. If they don't go in that way, there is a restriction in the hydraulic system or the pistons are sticking. Open the bleeder screw. If the piston goes in now, the hose could be constricted or the brake fluid is contaminated with petroleum product.

Hose constriction is more common on Chrysler products that use a metal anchor bracket in the middle of the rubber hose. Rust buildup inside where that bracket is crimped around the hose pinches it off. The brake will apply with heavy pedal pressure but will take a long time to release, (potentially hours). The pedal will be higher and harder than normal too. The fix is real easy and just involves using a large pliers to open the crimp a little. Another hint is the brake won't release when cracking open the line at the master cylinder.

If the piston will pry back after cracking the steel line at the master cylinder, fluid contamination should be suspected. Petroleum products, such as power steering fluid, engine oil, and transmission fluid causes rubber parts to swell. The clue is the bladder seal under the reservoir cap will be greatly expanded and mushy. The lip seals in the master cylinder also grow past the return ports and trap the fluid. As the brakes heat up, the heat transfers into the fluid which expands and since it can't flow back into the reservoir, it applies the brakes harder.

On Fords, it's more common to simply have rust pits or dirt on the pistons causing them to stick. You will not be able to pry them back even with the bleeder screw open. The c-clamp will get the piston to go in, but that rust or dirt will be under the square-cut seal. The way the seal is supposed to work is it tends to stick to the piston when fluid pushes the piston out to apply the brake. By sticking to it, it deforms or bends a little. When you release the pedal, the seal wants to straighten out. That's what pulls the piston in just enough to release pressure on the pads. As the pads wear down, the piston moves out a little further. The seal can only bend so far, so the piston slides a little through it. That's how it self-adjusts. When dirt or rust is on the piston, it will stick applied and refuse to release.

As for screwing the pistons in, that only applies to GMs and Fords with the parking brake built into the rear calipers. Once they are screwed in and the pads are installed, they will only come out by applying the parking brake. Regular use of the parking brake is required to keep the rear calipers in adjustment. Chryslers have always used a drum parking brake inside the rotors when the rear uses disc brakes. Some newer Fords are going that way too. It is a much simpler and more reliable design.

Caradiodoc

Ok I need you to do some testing. You will need a digital multi meter for these tests. First you will unplug the A/C cycling switch and then check the ohms of resistence between the violet wire and ground. Then with the a/c selector in the a/c position check the high pressure switch unplug the harness there and check the ohms between the dark blue wire with yellow stripe and ground too. Lets start there and see what we find. Thanks

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OK so far so good. Now there should be a violet wire at the A/C compressor switch. I need you to unplug that and check the resistance between the violet wire and ground should be 10k ohms or more if it is less then that then you need to check that wire for any breaks or shorts. If it is more then 10k ohm then you need to do the next step.
Plug the switch back in and back probe the violet wire with a paper clip and connect your meter between that and ground and then you will need to set it where you can see it from inside the car and then rotate the selector switch and put it in all possitions. If any possition is less then 10k ohms during this then the selector switch is no good. If all is good here then get back back to me and we will go to the next step. You are welcome I am a Ford and Mustang guy myselft. I also have a 98 Mustang V-6 with many mods and for summer and a 95 F-150 for winter. Glad to try to help. Let me know what you find.

OK no worries we will get this it just takes a bit longer to do this over the net as apposed to having the car infront of me. Now what I would like you to do is first check the a few fuses. Fuse number 2, 23, 24, they should be a 20 amp, 15amp and 30 amp in that order, these are in the fuse box inside the car. I also need you to check the black wire with the yellow stipe at the a/c clutch. This is the power wire to the clutch coils and with the car on and the a/c on max do you get power there? If not then you need to find the A/C relay in the relay box behind the engine coolant reservior and check that the red wire is getting power to the relay. If that is good then check the dark green wire with the orange stripe at the relay to see if it has power. If this don't have power then I need you to check the fuse in the junction box that is infront of the drivers strut tower. It is the 20 amp fuse for the a/c relay, make sure it is good. I know this is a lot to check and if you have any problems please just ask. Let me know what you find here.

Is it really running hot or is the temp sending unit not working. If you can have it checked with an inferred heat gun to see if its running normal temp or not first and we can go from there.

Ok no if you would unplug the ac clutch and check resistance across the terms of the clutch. Get back to me with what you find. So far sounds like a bad clutch coil. Thanks

Sorry your right some times I forget to read back to make sure where we are at. With that I need you to find the A/C clutch relay and the EDF relay next to it. These are in the relay box behind the coolant resersior. I am thinking that one of these are getting overheated and shutting down there for needing replacement. Everything else you tested checks out good so far so that is the only thing that makes sense. Once you find them then I need you to check to see if the pink wire with the yellow stripe to the ac relay get power when you turn it to ac. Then check to see if the EDF control relay get power from the dk blue wire. Let me know what you find.