I picked up a 04 JCW that was missing badly, but it was due for a tuneup. I swapped the plugs, wires, and coil and it runs great now but the CEL is still on and it seems down on power.

I hooked up a scanner, and the DME was reading as a diesel. It also showed a transmission control unit even though this is a manual. Nonetheless, neither are readable. I even tried INPA to no avail.

The code is a DE19 for the DSC, but it seems to be a ghost fault for something else. I just can't see it. I do have the airbag Isolation fault so I've ordered a resistor to address that.



I did pull the DME plugs and reseat them, but there was no change.

Am I missing something? Any ideas?

 

Check the dme in realoem to see if that is correct for your car? Check all grounds.

 

I looked at the grounds, and all look undamaged and on solid metal.

Good idea, I'll pull the DME and see if it's been swapped out at some point.

 

I first checked OBD pins 16 and 1, and both have power as needed. I then unhooked the battery to pull the DME so I could start checking continuity for a damaged or broken wire.

The date and part number on the DME is correct for the car, but there is no JCW label on it. It was a one owner car with all the paperwork so it is a true JCW, but I'm guessing the tech didn't add the label when he installed the kit.

 

And the last 7 of your vin match the dme? / guessing it does. Not sure how to check if there are no other internal errors. No bent pins, and no evidence of damage? I’ve had mine out a few times, and that looks clean. Try again?

 

Yes, the last 7 do match the car so no DME change it appears. The pins look good, and the DME appears to be in good shape and it was fairly clean inside the box. Nothing visually wrong or questionable.

I did check the violet/white wire from pin 7 on the OBD to pin 36 in the small DME, and there is continuity. For a sanity check, I also checked continuity between pin 7 and the round plug violet/white wire as well. There was no issue.

So there doesn't appear to be a wiring or continuity issue, but the DME is unaccessible. I'm still confused why it picks up the DME as a diesel unit and a transmission control unit. Both are unreadable, and I'm starting to wonder if the DME is corrupted or?

 

I wanted to add one more note.

When checking for continuity, I found that at the round plug near the headlight on the driver's side, I only had continuity on one side of that plug. The female side was good, but the male side had no continuity.

I then worked on tracking that plug end, and it seems to go to the PS. I didn't see an issue with that wire so not sure that helped.

Should the round plug at the front driver's side provide continuity to pin 7 on both sides or only one?

 

Final update, no further progress. I'm still unable to to communicate with the DME.

I did try pulling codes through the OBC, test 14, but all the tests gave 000000 so nothing gained there.

I'll mess with it some more on Sunday, but I did drive it up town today and it was great. That helps at least, lol

 

I messed with the car some more today, and I've made no progress.

I found a video online where a guy diagnosed a similar issue if not seeing the DME with considerable skill. It is different that my situation since the DME shows up as a diesel where his didn't show the DME at all

After watching the video, I rechecked all my ground and continuity again with similar results. I did try reading the DME again with the round plug disconnected just to separate out the PS run for the violet/white diagnostic wire and the results were the same.

I'm just not finding a wiring issue which unfortunately leads me towards the DME itself being corrupted in some way. Otherwise, I don't have another way of explaining the DME showing as a diesel and it having a TCU even though it's a manual.

How should I approach this repair. I don't want my DME cloned since it's obviously not right, but how do I get a new DME setup for my VIN and with the proper JCW tune?

 

Have you tried to reach out to the user "adrian" on this forum ? He may be able to assist . He is great with ecu mapping , so he may be able to give you better advice on why things are showing up the way they are .

 

I haven't yet, but he tuned my other Mini so I know he's solid. I just wanted to verify I didn't have any wiring issues before starting down another support path.

I'll reach out to Adrian to see what he says about the DME confusion. Thanks

 

I got with Adrian on the mysterious DME issue, and he wanted to connect to the car to see if he could figure out what's going on. Of course I needed my DCan cable, but it now appears that got lost in my recent move. Therefore, a new cable has been ordered and we are planning to sync up next week for him to take a look.