Hi guys,

I’ve got a 2015 XJR that’s been fighting me for the last couple of days and I’m at the end of my rope. Hoping someone here can help — possibly with a remote session.

A year ago the chassis control module failed. A local Jaguar shop replaced and programmed it. Ever since then I’ve had recurring issues where the car loses its adaptive dynamics “memory” and drops into P1905-00 (End of Line Test Mode). When that happens I also get E-Diff unavailable, CEL, and both Dynamic and Winter modes disappear.

Two weeks ago I finally bought an SDD setup and managed to fix it by running a suspension height calibration. The car was absolutely perfect again — no faults, smooth ride, everything working.

Then yesterday I made the mistake of opening an old session just to poke around. Something went wrong, and now I’m stuck right back in End of Line test mode. No matter how many times I run the suspension calibration or try to force customer mode, it won’t come out. The rear stays high/bouncy, adaptive is faulted, and E-Diff stays unavailable.

I’m brand new to SDD and thought I was being careful, but clearly I screwed something up in the config. I’ve tried clearing DTCs, battery resets, reloading old configs, and going through CCF Editor, but I can’t get the module out of test mode.

If anyone has dealt with this exact issue or is willing to remote in and take a look, I would be incredibly grateful. Happy to pay for your time or donate to the forum — whatever works. Just want my car back to normal so I can get back to work.

Thanks in advance, Aaron

 

Aaron

I have no idea I am afraid but have you seen this https://www.jlridssddmongoose.com/la...7-user-manual/ and



This thread seems to back it up https://www.rangerovers.net/threads/...solved.358280/.

Best of luck

 

Alrighty, update time — and a big slice of humble pie for Aaron.

Short version: I fixed it… by breaking it worse first, then fixing it again. Here’s the “don’t do what I did” PSA.

The car faulted into P1905-00 (End of Line Test Mode). Rear air suspension shoots to max “showroom” height, Winter Mode and Dynamic Mode vanish and can’t be selected, E-Diff says “not available” at all times. Annoying as hell.

Best guess: non-SDD scanners (like my Foxwell) don’t close protocols cleanly and leave the module in limbo. Loose internet theory, but it’s the best I’ve got.

Fix? Bought SDD and ran a suspension calibration. Car was perfect — no faults, smooth ride, everything golden.

Then I couldn’t leave well enough alone.

Opened an old session (I don’t know why), poked around in CCF Editor (engineering mode), saw a ton of stuff marked “undefined” that I knew my car had (adaptive damping, steering angle sensor, battery monitor, etc.). Asked Grok for help, got suggestions, started “fixing” them one by one.

Big mistake. Over-configured the crap out of it; my best guess at least. Car lost its mind: rear jacked high again, bouncy ride, adaptive fault, E-Diff unavailable — full P1905 loop. Six days of insanity trying to undo it. Calibrations would take and SAY everything was fine but not drop the rear, configs wouldn’t stick, endless timeouts. Nightmare for someone with a brain like mine.

Forum member GT40 stepped in and without going into too much detail about his wizardry, after a couple session, we eventually got it fixed.

TL;DR:

If you have SDD and engineering access, don’t just “play around” in CCF Editor unless you’re 100% sure what each flag does. Even with AI help, I walked way too far down the wrong path and turned a working car into a six-day nightmare. Stick to factory settings and change very little unless you know exactly what you’re changing.

Huge thanks to GT40 — absolute legend. You saved my sanity (and my car).

Aaron

 

So what did you do to fix it?

 

This is where you screwed up. AI can only make correct suggestions based off correct information already out there, and if the correct information is missing or incomplete, it will just make sh*t up. Which rapper said "don't trust none of what you read and only half of what you see"?
Don't trust AI for specialized diagnostics like this.

 

we downloaded the as built file from the servers, and then I did a line by line comparison and made my CCF match that as for whatever reason it wouldn’t push to the car.