2015 REX won’t start while driving

[Tbrown3313]

I have 2015 i3 REX. The ReX starts and runs fine with manual startup in emissions testing mode. It will not kick on while driving when needed. Any help is appreciated.

 

[rcpmac]

Not a power user here but what do you mean by "when needed"? At 6% remaining battery? I believe that is the programed state of charge trigger when REX kicks-in - at least it does so on my 2019

 

[Tbrown3313]

Yes, it does not kick on at 6%. It will continue to use electric power until it is completely dead.

 

[TedStriker]

Do you have 'hold state of charge' available? Any error messages?

 

[Bat66]

Just spotted this thread. I have a 2013 REX. IF I run the car 'cold' i.e. it has sat for a while the REX will not cut-in and I get the drivetrain failure error. However, if I start the engine and let it run a few minutes before a drive, it will maintain the battery level as it should and no error pops up. Again if I then stop for a coffee or something for too long a break, then get back in and drive the REX fails to cut-in and I get the drivetrain error.

Being a UK variant the maintain battery <=75% charge is by default an option, even if I don't have this set, at some stage while running the car just on battery it will again pop-up with the drivetrain error.

 

[Bat66]

My i3 is back and fully functional

After 8 days at Cragos, with the AUC and both ambient temperature sensors having been replaced, the ReX cuts in all on its own, and no errors show up on the displays.

I'm not sure why the paperwork stated, "PLEASE NOTE: Auxiliary engine will only cut in at 7% battery." Given that this is a UK European model, and by default, we have the ReX menu option to enable maintaining battery when at 75% or less, but...