15 Jeep Wrangler C121C. A verified repair using a flash update?
I do mobile programming and am amazed at some of the requests I get. (that can be a different discussion) I get a call from a shop that is a pretty regular customer with relatively good results. If you do mobile programming you know what I mean.
I get a call to program an ABS module on a 15 Jeep wrangler. New unit from dealer. I usually do not ask why, and I also did not this time. I get to said shop, and initialize the ABS module. All goes well until I am returning from the drive required. I get a traction control light. Check ABS codes. I have a C121C Torque request denied. The diagnosis is very basic. It comes down to either a new ABS module or a New PCM.
I see that there are updates for PCM and TCM. These are additional charges, and there is not a bulletin stating what this will repair. It is a roll of the dice for sure. After some discussion with the shop. The decision is made to go ahead and do the updates. There is also an oil control code. I do not remember for sure what it was. The shop was going to investigate after I was done.
After a 10 mile test drive it is decided both codes have been repaired by a PCM/TCM update. I am not sure which fixed it. They were both way out of date,
I just fine it interesting, AllData, Identifix both had the code description and diagnosis as module replacement. Tech authority did not even list the code that I could find. No suggestion for an update. Makes me wonder if it needed a ABS module at all. I am going with NO. I will never know for sure.
Hope this helps someone in the future.
The trouble tree looks very simple. It is probably accurate, they usually are. That said… Module replacement seems extreme for a code like that. I'm familiar with codes that directly specify communication faults between modules, actual internal module faults, and disable requests. Your code description sounds like a disable request, which is usually because the PCM has an issue and doesn't want…