ChatWithaNinja

Hey everyone, I've got a 2002 (with updated climate controls) that is having a low voltage signal going to the AC compressor.
Compressor is new. I just got the car and I got it for cheap because the AC wouldn't work. I could see the front of the compressor and it had a busted clutch.

I can turn on the new compressor with a straight wire directly from the battery and everything works fine.
I took it to the shop and they said the compressor is only getting 4 volts and needs 12v to engage.
They then quoted me a $300 labor charge (plus another $500 for new controls) to take apart the dash and test voltage coming out of the controls... I can easily take apart a dash myself, but I was wondering if anyone knew the pin-out on the controls so I can test voltage myself.
I'm picking it up today. I can easily get a $200 set of used controls off of ebay and just replace the one I have in the dash now, but I'm not going to spend that money if the voltage is coming out is fine from the controls and I'm dealing with a frayed wire somewhere...

I'm betting a wiring diagram is on this site somewhere but my searching isn't finding it.

thanks!

Maj. Dundee

When you get the truck back, remove the radio, then the Center Section of the I.P. and then the AAC Control Module.

Disassemble the AAC with a T7 Torx screwdriver and check for a burned circuit on the back of the circuit board.

ChatWithaNinja

Thanks!
Now I have the updated controls, so this will still work?

Maj. Dundee

Have no idea what you are talking about.

ChatWithaNinja

199x - 2001 use these climate controls (the same ones in your PDFs that you attached) that look like this:


While my controls (2002 +) look like the one I linked in the previous post. (ignore the arrows, that was just on the image already and have nothing to do with it)
It was just a question in case you already knew. I'm going to take them out and replace them.

ChatWithaNinja

OK... back for more.
So the AAC controls are good. I took them apart and they show no signs of blown fuses.
The system is charged correctly.
The compressor get a 4V signal, not the 12 it needs.
I hot wired the compressor direct to the battery and ran it for 5-10 seconds (until my daughter yelled COOL!!)
I have an iCarSoft reader and the only reading I see that might be of use is the "A9 (AC Compressor) 35%"
not sure if that is in spec or what...

I've read that the pressure/temp sensor can be faulty and not reading right. I'm down to that really... Unless anyone has other ideas?
Please?

Thanks!!

ChatWithaNinja

Pic

Maj. Dundee

Is your reader capable of extracting codes in the AAC?

ChatWithaNinja

Yes i have the following:
b1302
b1108
b1105

Maj. Dundee

After you replaced the compressor, did you fully charge the system with refrigerant?

Did you clear the codes after recharge?

Check the operation of the Coolant Cir. Pump. Turn the key to pos. #2 and feel the pump with your hand to see that it vibrates.

ChatWithaNinja

Yes, the system was fully charged.
I cleared the codes after I read them. No change.
I'll check the pump to see if its working when key is on.

Thanks!

edit: key to "on" but not running?
AC on full auto?

ChatWithaNinja

update:
there is no sound or vibration at all from that pump in the picture you attached. I even got a long flathead screwdriver and placed it on the pump and put it to my ear with the key to "on" and I could hear the fan blowing full inside, but nothing from the pump.
I checked the codes and the only one (other than a flap code) left after clearing is the B1108
pic attached.

ChatWithaNinja

Pic

Ignore the 2/5 notation. this was when I took pics before clearing codes.

Maj. Dundee

What is the flap code # and what is the description of it?

ChatWithaNinja

All codes and info i could pull off of the carsoft
all info was pulled while car was running in park and AC on auto

Maj. Dundee

Is this the control that is in your truck?

Maj. Dundee

I can't believe that I ignored this code. It is either for the Coolant Cir. Pump and or the module box Blower Motor.

With the key out of the ign. check both contacts for 12v at fuse #5 in the right side kick panel fuse box.

ChatWithaNinja

Negative. I have the 2002 updated controls.

ChatWithaNinja

The fuse looks good.
the key is out and I am getting 12v on the bottom slot and nothing on the top - so yes, I am getting power to the fuse.

Maj. Dundee

Pull the fuse and if it looks like the image, it is blown. Pull it and replace it.

ChatWithaNinja

yeah, the fuse is good. I've checked ohm.
I'll replace it for confirmation anyway.

So if I have a bad coolant circulation pump, would that cause the AC to not come on?

And I am not familiar with the "module box blower motor" - what and where is that and what is its function?

Maj. Dundee

You said that the fuse only showed voltage on one contact and not the other. That means that the fuse is blown. Something is wrong.

ChatWithaNinja

Sorry, no. The fuse block showed voltage on one slot but not the other. 12v current is going to slot 1, then it hits fuse, then it goes out slot 2. when I removed the fuse, that was what I got. 12v current coming out slot 1 and nothing in slot 2 (no short circuiting with 12v going to both end of the fuse).

Maj. Dundee

I have no idea what you are trying saying, none whatsoever. There is no current involved, just volts.

Do you get 12v when you test both contacts? Yes or no.

ChatWithaNinja

So I have been a shade tree mechanic for 30 years and I have messed around with fuses on my life and never once did I realize that there were slots on the top of the fuse that you could check the volts without removing the fuse. I thought you said that I needed to remove the fuse and measure volts going to the fuse from the fuse block which is why I said 1 slot on the fuse block has power the other does not.

thanks for showing me something new! Even though I really should have known it a long long time ago LOL

yes I am getting 12 volts on both side of the fuse