08 Dakota / Cummins A/C help

[evguy1]

Just did a scan of the climate control module and it looks good.

[evguy1]

Just found code B1035 INFRARED TEMPERATURE SENSOR HIGH in the overhead module. I did a search for info and get very little on what it is and location.
Any idea what this is and where I find it?

[tbirdtbird]

"I should mention that the whole A/C system is the stock Dakota system so there should be no compatibility issues."
Meaning every single component is stock including the compressor? You adapted the comp to the Cummins?
Seems to be new info that this is an engine swap. I wondered how a Cummins got into a Dodge
How did you get the stock ECU to synch with the Cummins incl for the rest of the controls such as CPS, etc? That is always the hard part with swaps

[evguy1]

Yes, just fabricated a mount for the Dakota compressor. Replicated the CPS on the front of the Cummins. The Dakota ECU is just a driver for the other modules and is not tied to the Cummins ECU. The Dakota ECU is "Happy" with no DTC's.

Blacky engine.jpg (196.03 KiB) Viewed 3885 times

[evguy1]

Looks like this may be the or a problem to look at tomorrow.
The infrared temperature sensor is located in the overhead console and consists of an infrared transducer concealed behind a clear lens (2) in a molded plastic housing with an integral wire connector receptacle (1) and mounting tab (3).

The infrared sensor is used only on models equipped with the automatic temperature control (ATC) heating- A/C system.

[evguy1]

That was easy, was able to just go into the body control module and turn off ATC and the sensor error went away. I have pinned all the harnesses to be sure they are getting signals where they need to go, can see the BCM request that the ECU turn on the AC relay but it wont. I confirmed that the AC relay has 12V to the contacts and has 12V on the signal pin #85, just missing the ground signal from the ECU on pin #86. If I ground the signal wire the compressor turns on. ECU must still not be happy, just like me.

[evguy1]

Well, I'm beat,I admit defeat. Today I converted it all to manual. Basically just a pressure sw and core temp switch on the ground side of the stock compressor relay and the stock keyed / fused power on the positive side. I ran it this way for years in the past but was determined to make the stock system work. Had it all up and running in a few hrs. Still need to get it evacuated and recharged but at least the controls are in and working. I think I can make the stock dash switch work when I have a bit more time which would be nice. Just need a couple of transistors to run the 12V compressor relay off the stock switch which is 2V. I just wanted to put a bow on this subject as I hate reading this sort of thing and then find they never concluded the thread. Thanks for the ideas, I'm sure I will be back.

[tbirdtbird]

IMO the control circuits on modern day MVAC are over engineered thus making the system prone to failure

[bohica2xo]

EV Guy, you have more patience than I. And that BCM put up a hell of a fight.

Round two should be very educational. Thanks for sharing all of that.

So how does the bread truck motor work out in the Dakota?

[evguy1]

The engine has been amazing. This truck has towed our 20 foot fifth wheel all over North America for the last 7 years. Its not the old mechanical 4BT but the newer common rail ISB170. Lots of power and 22 MPG towing.
https://youtu.be/qe6sHb1FDlA