I took a look around the forum for this but haven't zero'd in on it. Anyone know what an MSA Controller is? If so, where's it located on the vehicle? I was perusing the service manual for the 1998 XJ, specifically trying to figure out how the CEL light is turned on. Looking through the wiring diagrams for all things tripping the the MIL (Malfunction Indicator Light). I see various references to the MSA controller being the source for it but it isn't described in detail.

Last weekend I replaced the TCM and for 4 days the CEL light remained off. Then, on the 5th day it returned with the same code that the previous TCM flashed (0740). The problem I have is not the TCC solenoid not locking out. The transmission is shifting normally and going into lock-out when it's supposed to. I bought a new (different) OBDII reader and it's specifically calling out an open circuit. But which open circuit? If the TCM is locking out the transmission normally, what's tripping code 0740? If the TCM doesn't trip code 0740, what does? I'll trace that circuit.

 

You own a 2.5 TD?
Found this.
Just a pin out illustration but maybe it does resemble what it looks like and help you find it.
Look at Post #10.

https://www.jeepforum.com/forum/f11/...ntina-3486178/

 

Thanks, Ralph, but I'm an idiot and locked onto what I thought was a feature of my truck. I was wrong. Sorry to send you goose hunting out of season. I've had the opportunity to drive the 98 XJ (my son's) for a few days to monitor the codes and find that the 0740 code is intermittent. What was throwing me off was I wasn't thinking about the problem correctly. Once the code is tripped and latched it stays that way until corrected/cleared. Well, I'd do a little work and then clear the code. My son would not report back to me immediately when the CEL illuminated again after clearing the code so I wouldn't know exactly when it tripped again after each time I attempted a fix. Now that I've had the truck for a few days I can see that the problem is intermittent. Sometimes it takes a few miles to reappear, sometimes a few days, so there's definitely a wiring issue between the TCM and the TCC solenoid. I'm going to drop the pan next weekend and, starting with the connector, work backwards with a meter while jostling the harness. Until then, pulled the CEL bulb because it drives me nuts. I keep an OBDII DTC reader in that truck.

 

No problem.
I was out of depth with that question.
To be frank I never heard of a MSA controller before and was curious.
So I poked around a little thinking maybe I would learn something.
To be even more frank still not sure what it is. LOL.
Now that you posted the code I recognize it as a tranny code but that is about all.
Oh and thinking pulling the bulb was overkill.
Way back when in the '80's GM's I used to drive we used electrical tape. LOL.