FabricGATOR
Member
- Joined
- Jul 1, 2023
- Posts
- 84
- Reaction score
- 25
- Ram Year
- 2004
- Engine
- 5.7 Hemi
It is hot in there, most of the time, ...
Hey guys, I am new RAM 3rd gen but Mopar for years. I even rebuilt my own 41TE/A604 transmission. I am am also an hvac 609 tech.
So my brother gave me his 2004 1500 SLT that he bought new at the dealer, gave it to me just last Wednesday while I was visiting. He said it was hot in there and he just wants a new Toyota or something with a backup camera and sensors... I think he is crazy, new cars suck!
I rented a uHaul trailer and towed my car home in Florida with the truck (in late June 2023, for timestamp reference). I love my brother and I love this truck BUT the a/c would only work about 38% of the time and it almost seemed like it is tied to the window switch as when it starts to blow cool and I put up the windows, that is when it quits again...
It is certainly an electronic / electrical gremlin as IF/WHEN the compressor engages, it is almost too cool.
BTW, the windshield wipers are also inop. It had a CEL that was [power steering switch] and [PS pressure parameters], I put fluid in and it went away.
Oh yeah, I checked the fuses and played musical relays with AC related circuits. The first time I did it with the A/C clutch, I thought '' well, that was easy'' NOT!
I am a troubleshooter not a parts changer and I HATE the parts canon approach. Doing that can get real expensive real fast.
I evacuated and recovered and then put in the measured charge (well, I tried) as when it came time to start the engine to suck up the remaining charge from the machine, the darn clutch wouldn't engage. I thought for sure that I really broke it now BUT the next day when I returned to try and figure this out, low and behold, the clutch was engaged and the vents were blowing cool... of course the machine with the remaining r-134a was five miles away... When I get it all working as it should I will go and pull another vacuum and charge. A long, deep vacuum...
My initial thoughts were that someone had been messing with a Walmart 134 charge hose kit and likely put a slug of air into the system. Step one, put a known measured charge into the closed system.
My friend has a auto repair shop and all the good tools including Snapon and Autel scanners. The Autel I had didn't give me the ability to manually engage the clutch so I didn't finish the charge but I did change the receiver drier and both Schrader type service valves while I had the system empty.
This thing is killing me, there aint' nothing that is free AND easy.
These scanner shots are from the HVAC sections. I would read them, take a picture, then clear them and see what came back as a hard code.
I found this forum while searching for FSM and IPC and I studied it all day.
What I need is the Dodge/Mopar/RAM Body Diagnostic Procedures manual so I can get the values and procedure to check the refrigerant pressure switch and the evaporator temperature sensor.
My bet (my hope) is that it is one of those. And while the pressure sensor can (should) be able to be changes without evac the system, the evap temp sensor may need me to remove the airbox behind the dash, if not the sensors, then the PCM or the climate control head... I gotta be sure before I spend that kind of money.
IS ANYBODY able to offer insight, experience, or solution?
I am old school and when it comes to electronic controls, that is where my skillset runs a bit thin...
Cheers
BTW, I worked at this shop in the past and they would start throwing parts at it to see what fixes it. not cool.
Hey guys, I am new RAM 3rd gen but Mopar for years. I even rebuilt my own 41TE/A604 transmission. I am am also an hvac 609 tech.
So my brother gave me his 2004 1500 SLT that he bought new at the dealer, gave it to me just last Wednesday while I was visiting. He said it was hot in there and he just wants a new Toyota or something with a backup camera and sensors... I think he is crazy, new cars suck!
I rented a uHaul trailer and towed my car home in Florida with the truck (in late June 2023, for timestamp reference). I love my brother and I love this truck BUT the a/c would only work about 38% of the time and it almost seemed like it is tied to the window switch as when it starts to blow cool and I put up the windows, that is when it quits again...
It is certainly an electronic / electrical gremlin as IF/WHEN the compressor engages, it is almost too cool.
BTW, the windshield wipers are also inop. It had a CEL that was [power steering switch] and [PS pressure parameters], I put fluid in and it went away.
Oh yeah, I checked the fuses and played musical relays with AC related circuits. The first time I did it with the A/C clutch, I thought '' well, that was easy'' NOT!
I am a troubleshooter not a parts changer and I HATE the parts canon approach. Doing that can get real expensive real fast.
I evacuated and recovered and then put in the measured charge (well, I tried) as when it came time to start the engine to suck up the remaining charge from the machine, the darn clutch wouldn't engage. I thought for sure that I really broke it now BUT the next day when I returned to try and figure this out, low and behold, the clutch was engaged and the vents were blowing cool... of course the machine with the remaining r-134a was five miles away... When I get it all working as it should I will go and pull another vacuum and charge. A long, deep vacuum...
My initial thoughts were that someone had been messing with a Walmart 134 charge hose kit and likely put a slug of air into the system. Step one, put a known measured charge into the closed system.
My friend has a auto repair shop and all the good tools including Snapon and Autel scanners. The Autel I had didn't give me the ability to manually engage the clutch so I didn't finish the charge but I did change the receiver drier and both Schrader type service valves while I had the system empty.
This thing is killing me, there aint' nothing that is free AND easy.
These scanner shots are from the HVAC sections. I would read them, take a picture, then clear them and see what came back as a hard code.
I found this forum while searching for FSM and IPC and I studied it all day.
What I need is the Dodge/Mopar/RAM Body Diagnostic Procedures manual so I can get the values and procedure to check the refrigerant pressure switch and the evaporator temperature sensor.
My bet (my hope) is that it is one of those. And while the pressure sensor can (should) be able to be changes without evac the system, the evap temp sensor may need me to remove the airbox behind the dash, if not the sensors, then the PCM or the climate control head... I gotta be sure before I spend that kind of money.
IS ANYBODY able to offer insight, experience, or solution?
I am old school and when it comes to electronic controls, that is where my skillset runs a bit thin...
Cheers
BTW, I worked at this shop in the past and they would start throwing parts at it to see what fixes it. not cool.