How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask -Brad- Your Own Question
-Brad-, Dodge Dealership Tech
Category: Dodge
Satisfied Customers: 7827
Experience:  16 Yrs Chrysler/Dodge Technician. ASE Master Certified(L-1)
Type Your Dodge Question Here...
-Brad- is online now
A new question is answered every 9 seconds

I have a 04 dodge ram 2500 CTD, the problem im having is

Customer Question

Hello I have a 04 dodge ram 2500 CTD , the problem im having is that my AC dosnot come on the lights on the control are light , checked the relay is good , fuses are good , jumped the relay socket and the clutch turned on . Am I missing something? Checked the wiring diagram all I can see is the PTC ,where is that?
Submitted: 1 year ago.
Category: Dodge
Expert:  -Brad- replied 1 year ago.

Can I have the last 8 of your VIN to grab a wiring diagram?

Customer: replied 1 year ago.
Expert:  -Brad- replied 1 year ago.

I attached the wiring..

Can you remove the ac clutch relay and tell me if pins 30 and 86 have 12v? And then see if 85 has a ground when the a/c is on?

Customer: replied 1 year ago.
pin 30 and 87 have 12 v , pin 85 has ground,
Expert:  -Brad- replied 1 year ago.

Are you sure? 87 goes to the compressor and shouldn't have anything on it... Can you double check and tell me if 86 has 12v and 85 a ground? If they do then check for 12v at the compressor when a/c is on..

Let me know

Customer: replied 1 year ago.
pin 30 and 86 have 12v and 85 no ground when ac on .
Expert:  -Brad- replied 1 year ago.

Ok so the PCM is not telling the compressor to engage.. And reasons the PCM will not engage the a/c clutch are bad pressure sensors, or low on freon.. Is it full of freon?

Customer: replied 1 year ago.
I thought at first that was the reason but when I removed the relay and jumpered pins 30and 87 the compressor turned on and it was pumping cold air , so temporarily I wired a switch across it so I could have air for awhile but I want to get it fixed . By doing this will I burn the compressor?
Expert:  -Brad- replied 1 year ago.

You could possibly burn up the clutch if it does have a very low charge. The correct way to repair this issue is to recover the freon and check for proper charge and then if monitor the pressures with a scantool.. Most of the time I find a low charge is the reason.. Also when you add freon also add UV dye because there is a leak somewhere and you need to fix it. Once you run it a while check over the entire system until you find the green stuff, then repair it..

Also if you can't find any leaks check your drain, if dye is there your evaporator is leaking and the dash will need to come out.. Another very common issue...

I hope this helps,