A/C Relay Location

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

OP
OP
BAMF

BAMF

Senior Member
Joined
May 29, 2016
Posts
206
Reaction score
124
Location
Southern Louisiana
Ram Year
2015 Big Horn
Engine
Hemi 5.7
I was inquiring about the fan inside the truck, it should be on high and keep the windows down.
Usually the condenser fans turns on low any time the AC is running. Your sorta running blind without knowing at least the low side pressure, both would be better. I think you can use AlfaOBD to see if the fan and/or compressor is commanded on.
It wasn't till almost the '17 model year that trucks had the cabin air filter installed from the factory. Sometime during the '16 model year the filter door was being installed but no filter (yes a bunch of people went WTF?)

Yes sorry. I had the fan in the truck on high. I just drive to town and back about 60 miles and the a/c never kicked on.

My compressor fan is not coming on either.... I didn't even realize it was there.... Its hard to see that far past the shroud

Sent from my SM-N975U using Tapatalk
 
OP
OP
BAMF

BAMF

Senior Member
Joined
May 29, 2016
Posts
206
Reaction score
124
Location
Southern Louisiana
Ram Year
2015 Big Horn
Engine
Hemi 5.7
I was inquiring about the fan inside the truck, it should be on high and keep the windows down.
Usually the condenser fans turns on low any time the AC is running. Your sorta running blind without knowing at least the low side pressure, both would be better. I think you can use AlfaOBD to see if the fan and/or compressor is commanded on.
It wasn't till almost the '17 model year that trucks had the cabin air filter installed from the factory. Sometime during the '16 model year the filter door was being installed but no filter (yes a bunch of people went WTF?)
The condenser fan was not working. I pulled the relay for that and swapped it with the air suspension relay (that my truck isn't equipped with). The fan came on and the compressor clutch engaged..... Hopefully that has been the problem all along. I wonder if the compressor uses the same relay as the fan.


Sent from my SM-N975U using Tapatalk
 

Burla

Senior Member
Joined
Apr 28, 2012
Posts
27,545
Reaction score
57,766
Ram Year
2010 Hemi Reg Cab 4x4
Engine
Hemi
Thanks, Burla.

Yes the clutch is 62 but that's just a 10 amp fuse not a relay. I wonder where that additional fuse block is.... It has HVAC but that looks like a fuse too.
If it was intermittent it shouldn't be a fuse I wouldn't think.
I just don't get how every other vehicle I have looked at except this one has a relay with the rest of the fuses.

Sent from my SM-N975U using Tapatalk
The condenser fan was not working. I pulled the relay for that and swapped it with the air suspension relay (that my truck isn't equipped with). The fan came on and the compressor clutch engaged..... Hopefully that has been the problem all along. I wonder if the compressor uses the same relay as the fan.


Sent from my SM-N975U using Tapatalk

cool, so you are up and working. Kinda surprised that did, I guess you were right.
 
OP
OP
BAMF

BAMF

Senior Member
Joined
May 29, 2016
Posts
206
Reaction score
124
Location
Southern Louisiana
Ram Year
2015 Big Horn
Engine
Hemi 5.7
cool, so you are up and working. Kinda surprised that did, I guess you were right.
It didn't work.... Took it for a test ride last night..... A/C stopped working after about a 15 mins drive.

Sent from my SM-N975U using Tapatalk
 

Wild one

Senior Member
Joined
Jan 17, 2016
Posts
23,721
Reaction score
54,483
Ram Year
14 Sport
Engine
5.7
It didn't work.... Took it for a test ride last night..... A/C stopped working after about a 15 mins drive.

Sent from my SM-N975U using Tapatalk

I'm guessing you can rule out the relay,why don't you take it somewhere where they can hook up to the new A/C fittings and check the charge.I'm no A/C expert but to me it sounds like it's acting as if it's low on Freon,and the trucks are famous for leaking Freon from the accumulator o-ring
 

Burla

Senior Member
Joined
Apr 28, 2012
Posts
27,545
Reaction score
57,766
Ram Year
2010 Hemi Reg Cab 4x4
Engine
Hemi
It didn't work.... Took it for a test ride last night..... A/C stopped working after about a 15 mins drive.

Sent from my SM-N975U using Tapatalk

well ****, junkyard compressor, condenser whatever they call that dohicky.?
 

Burla

Senior Member
Joined
Apr 28, 2012
Posts
27,545
Reaction score
57,766
Ram Year
2010 Hemi Reg Cab 4x4
Engine
Hemi
That relay actually sends current through the TIPM board as well?
 
OP
OP
BAMF

BAMF

Senior Member
Joined
May 29, 2016
Posts
206
Reaction score
124
Location
Southern Louisiana
Ram Year
2015 Big Horn
Engine
Hemi 5.7
I'm guessing you can rule out the relay,why don't you take it somewhere where they can hook up to the new A/C fittings and check the charge.I'm no A/C expert but to me it sounds like it's acting as if it's low on Freon,and the trucks are famous for leaking Freon from the accumulator o-ring
I was starting to think the same thing.... I got a can of freon. The next time my compressor kicks on I will check the pressure.

Sent from my SM-N975U using Tapatalk
 
OP
OP
BAMF

BAMF

Senior Member
Joined
May 29, 2016
Posts
206
Reaction score
124
Location
Southern Louisiana
Ram Year
2015 Big Horn
Engine
Hemi 5.7
Just for a little closure if anyone has this problem in the future. It ended up being my wiring harness going to the compressor was jacked up, that's why it would work sporadically.... Thank you Louisiana roads!

Sent from my SM-N975U using Tapatalk
 

mndavec

Junior Member
Joined
Nov 25, 2025
Posts
1
Reaction score
2
Location
RDU
Ram Year
2017
Engine
Hemi 5.7
Did anyone find the relay? In my 2017 the A/C seems to be stuck on. Is it part of a control board and not a replaceable relay?
 

Attachments

  • IMG_6022.jpeg
    IMG_6022.jpeg
    415.7 KB · Views: 0
Back
Top