E5Farmer

Well I was hoping it to be something I could do myself. After catching up on the thread it looks like I might have to bring it in.

Interesting. So dumb question, What part should I look into replacing or testing? The TSCM? I apologize I’m not much of a mechanic but thank you for the help.

YUP! I was told dealers do not like to work on them. Luckily i have a couple local shops that don’t care.

That sounds like a good possibility. Would that be a computer fix you think? Or clutch job?

I cannot say it is something from the delete or not as it was deleted when i bought it was doing this since i brought it home. It could possibly be the reason he sold it. But what i was told is they were going away from automatic trucks on their farm. This issue could very well be the reason. I’m guessing its fixable, just getting to that point! Thanks

Yes i would agree. The truck runs fine 99% of the time so I’m not going to be spending big $ bringing it to a dealer or anything. Just every now and then it does this. I figured I’d try figure it out during the off season.

I have only owned the truck for a couple months and it was deleted when i purchased it, its been doing it since day one. I originally thought it idled too low.

The truck is deleted if that answers the question. It’s a new to me truck

Thank you. The truck is deleted

Thank you. I wish i could upload the video so guys could see and hear it.

Yessir

New to me 2012 CXU Mdrive with MP7. Truck starts, runs, drives fine. But when ever I come to a stop and set park brake it’ll start “surging” or “erratically idle” going from 600 to 700rpm. It does eventually work out if it. It will be idling at 650, set the park brake then immediately goes under load or bogs down to about 600 for maybe 1/4-1/2 second then let’s go and idles up to 700 then the process just continues, bogs down to 600 then “let’s go” and surges to 700 over and over. I tried disconnecting the throttle potentiometer behind the pedal but it continued. It does seem like it only does it after the truck is warmed up. I do have a video but it is too big to upload to here. thank you

12 CXU613. Problem, cannot control temperature of air coming out of vents in cab(always hot). Also cannot control the mode (vent, defrost, feet,etc…) I can control the fan speed itself. I have replaced the control unit itself, I put in a new actuator in the dash, neither have fixed it. The relay in fuse panel on the dash has power. I am not familiar with wiring of these trucks but I’m assuming if it was a fuse I’d lose all control including fan speed, Not just temp and mode. Any and all suggestions appreciated! thank you

I have a similar problem. Cannot control the temperature or modes. Replaced the control unit. Have actuators but I’m wondering if it could be the resistor?

Thank you for the information I saved all of these. Thank you very much!

Where do you find online manuals like this?

Thank you. That looks like good information

I am wondering if power only comes in on the fan control side? Maybe it is my controller that is bad? I cannot seem to find a wiring diagram on this thing. Mack seems to keep things locked down tight. (First Mack truck for me)

New to me 2012 CXU613. MP7. Both my cab temp and mode(vent/defrost) controls are not working. Fan control works as it should. Just always blows HOT air from the vents. I was told actuators buried in passenger side dash. But the temp actuator has been on back order for months. I raise an eyebrow when BOTH of them are not working. I checked fuses on top of the dash and fuses underneath by brake pedal. (Don’t have fuse diagram, checked all of them). All are good. It looks like their is a harness going to fan control and one opposite for mode/temp control? If I turn key to on position I cannot get any constant power from any of the terminals out of the wiring harness. Go ahead and replace all the actuators like was suggested? Or can you think of something else? Any thoughts are appreciated.