Dodge Cummins Diesel Forum banner

1 - 12 of 12 Posts

·
Registered
Joined
·
3 Posts
Discussion Starter #1
2006 mega cab 5.9 with AC that works great up to about 80 out side temperature then blows hot. I’ve been to the dealer 3 times and of course it’s never hot enough to cause the ac to stop. Dealer says system is charged, functioning, and there are no codes. When the ac does stop blowing cold the compressor or clutch is not working. Is this a sensor, or computer, or something else?
 

·
Registered
Joined
·
873 Posts
What does the engine temp look like when this is happening?
 

·
Registered
Joined
·
3 Posts
Discussion Starter #3
What does the engine temp look like when this is happening?
199 degrees. Should have added that I replaced the engine cooling fan, ambient air sensor, and high pressure transducer. The fan is now locking up when the ac is on even when it’s not blowing cold. I replaced the others just to see if it made a difference, it didn’t.
 

·
Registered
Joined
·
873 Posts
The fan should lock when the a/c is on. Shouldn’t matter if it’s working or not. 199* is within proper range so the ecm shouldn’t be using that excuse to stop the a/c. I am not sure what else could be causing the issue.


Maybe @rghavana knows of something? He has a lot more technical knowledge than I do.
 

·
Trying to learn
Joined
·
5,874 Posts
On a hot day, I would drive truck till up to temp park in my driveway with the engine running and AC on.
If AC is blowing hot air:
Test for voltage to the compressor clutch.
If you have 12v to clutch and not engaging, replace the clutch.
If no voltage, I would have to find the proper diagnostic procedure, might be in the FSM.
Not my area of expertise, so hopefully someone who knows will show up.
 
  • Like
Reactions: rghavana

·
Trying to learn
Joined
·
5,874 Posts
The dealer should have done that when he took it in but who knows.
 
  • Like
Reactions: rghavana

·
Premium Member
Joined
·
5,710 Posts
Yeah you would think, if no codes normal pressures, I would guess too much oil or blend door issue.
 

·
Registered
Joined
·
278 Posts
I had the same problem! It ended up being the connector under the oil filter. I hard wired that connector. I tried cleaning and adding dielectric grease several times but it would fail again after a month. There are several problematic connectors that effect the AC compressor. The fan clutch connector (fan speed) and the pressure switch connector located near the compressor. Clean the connectors with contact cleaner and add dialectic grease.
 

·
Registered
Joined
·
960 Posts
Could be the TIPM going south. Use a test light to check voltage at the compressor. You could be getting 12 volts on your test meter, but no amps.
 

·
Registered
Joined
·
13 Posts
2006 mega cab 5.9 with AC that works great up to about 80 out side temperature then blows hot. I’ve been to the dealer 3 times and of course it’s never hot enough to cause the ac to stop. Dealer says system is charged, functioning, and there are no codes. When the ac does stop blowing cold the compressor or clutch is not working. Is this a sensor, or computer, or something else?
I have the exact same problem on my 06 non mega cab.. Its the coil on the compressor..works perfect when its cooler and as soon as it gets hot clutch won't engage.. Im purchasing a new comp for about $210 ,it seems easier than tearing apart the old comp and indtalling a new field coil
 
1 - 12 of 12 Posts
Top