I've been having this problem for a while and so far all my efforts have not fixed it. I have a Reverant built MS2E from 2012. In 2016 I shipped it to him for installation of one of his CAN bus modules. Last year on the way home from MATG I had the CEL popping up (steady light). After some hunting I figured out my coolant temperature sensor was bad and replaced it. Fast forward a few months and I started getting the CEL popping up again. It appears completely random, sometimes it shows up within a couple of minutes from starting, other times not at all. I have checked my wiring to the MS but found no issues. Just to mix it up even more, a couple of days ago the Battery light came on. The battery is only three months old, and the car is running/starting fine so I don't see that as being a problem. I do not have a listing of what Reverant has the CEL rigged to light for, that would be helpful in figuring out what might be the cause (I wrote to him but in looking at past messages with him, my e-mail causes problems with my receiving messages from him).

I have searched around in here and not found anyone else with this problem. It has me pulling out my hair, and I don't have that much left as it is. Any ideas on what I can do to fix this would be greatly appreciated.

 

Not sure if the firmware on MS2E is different from the MS3 CEL, but in MS3 there's a menu in TunerStudio for selecting what the CEL activates for. There's not a whole lot of options, so it should be easy to take a datalog and check all the fields that the CEL looks for to see if anything is out of range.

 

I came across that during my searching and got all hot and bothered. Unfortunately I do not have the function on my unit.

 

Can you provide a log from when it's lit?

 

I'll get one today to post, just to make sure I have it recorded (watch, the damn thing won't light for me).

 

Was out running errands and was able to take three logs. Naturally the CEL did not light. However, the battery light came on almost immediately upon starting the car for the third log (after I started the logging). I looked at the recorded voltage and it was between 14.0-14.2 volts the whole time. More puzzlement.

 

Had her down for some maintenance pre-MATG. Got her out again today and ran a log, bingo! About four minutes after starting the log the CEL popped up. I scanned through the parameters and don't see anything wrong, hopefully someone who has more knowledge than I do can see something.