So driving along at lowe speeds in city driving I got gearbox fault, trac control unavail, and engine fail safe mode. I got no acceleration. I coasted to a parking spot and figured my number had come up with the ZF gearbox. A local transmission guy who works on ZF every week says the transmission is not the problem and he could not repeat the experience after two days of driving off and on. Suspects there is a communication problem with the computer.

I did notice that when I restarted to load on a flatbed, the gears worked fine but that I got weird "check rear brake lights" but they were normal.

Anyone out there with similar experience? What's the fix?

All ideas welcome!

 

Could be a power/ground/battery problem.

Look for codes in all the modules. OE-type tool needed.

You could also Search for people who've had one or more of the same issues.

 

The plot thickens a bit: Got fail safe, limp home mode again and gearbox fault. Shut down and retarted and it went away for 30 mins. Repeat and the same. This time it gave codes P0430 and P1122. But both codes cleared themselves and hour later.

Any thoughts?

 

P0430 may mean any of the usual stuff (cat failing, O2 problem, ...).

P1122 looks to be (accel) pedal position fault. Causes limp mode.

Free download workshop manual gives details.