Hi All,
Firstly thank you to everyone on here as I wouldn't be this far on without many of the threads on here.

So the stop start on my 2013 XFR has worked once since I bought the car six months ago. It's not a biggee as I'm working from home / not commuting at the moment (for obvious reasons). However its one of these things that is niggling at me.

I have; changed both batteries, reset the BMS, reset the ECU learned parameters, and re-calibrated the throttle position. After all of this I have now got to a position where the car runs and shifts a lot nicer and the PCM isn't inhibiting the stop start for any reason I can see. I've uploaded a readout of a short drive cycle so you can see the parameters I've been watching for diagnostics with my iCarsoft CR. Theses are the only ones I can see that are relevant to the SS functionality listed in the PCM. However SS still ins't kicking in.

The only thing that reads oddly to me is that the "Transmission control module economy stop/start request status" says "----- No request" at rest, and "Stop inhibition" when a "stop inhibited" flag is set. I don't know if that's normal... I cant see anything in the TCM parameters that talks about stop start, but I might have missed something. Are there any other places to look w.r.t. stop start diagnostics?

Anyway, does anyone have any ideas? Any constructive feedback would be much appreciated. For info there a re no faults registered on the car, apart from the heated front seats not working and the control module for that not responding on the bus (see separate post).

Cheer
Barry M

Note: Re posted from UK forum as I couldn't see how to move it here...

 

after fitting new batteries and other small issues, my start/stop worked fine

i have noticed that with the aircon on , it will work, but if the fan speed is set one notch higher , it wont activate, also , if i had heated/cooled seats on or other heavy loads the car also over rides this function

so its a learning process of what the car is doing and why

i have also noticed that the car wont start/stop when i first drive off in the morning for around five minutes , i presume the operating temp etc art at nominal

i have also sat in traffic with the start/stop activated with my foot on the brake, but then the car will start, i presume voltage levels drop so it initiates a start to bring in the alternator even though im still stood still

hey , im still saving fuel when it does work,

BB

 

Thanks BB​,
Yeah it's a very complicated system it even looks at drivers seat belt status among other things! I'll figure it out eventually. One of the things that caused an issue for me was that the throttle wasn't calibrated within the expected range.

Thanks again :-)
Barry M