Electronic hi-jinks with the Partner today

That is a massive range!

They have a bigger range than that, from the light off point to a regeneration point can be from 150-700C.

light-off

OH got home from shopping about an hour ago - said handbrake red light came on and consistent beeping. Took it out for a quick test, turned the heated seats off and fan down, and light went off and it stopped beeping. Turned fan on to 3, started again, down to 2 and stopped. Thinking it could be a voltage/alternator issue, but car electronics are so complicated . No OBD fault codes come up. Anyone any ideas?

How old is the battery.

New about a year ago

Tried a voltmeter across the battery to test alternator output?

Yep, looks reasonable at over 14v, now wondering if it might be a duff battery…just put it on charge and its taking well over 3A.

It wouldn’t be unheard of, I had one in a BMW 760 which I replaced because I was getting all sorts of weird warning lights and 3 months later it went stranding me, like a lot of cars nowadays it was a dealer change as it had to be coded to the car to reset the variable smart alternator output.

Good grief Colin, what a PIA

I’m pretty certain that a battery is still a battery even in a BMW - what has changed, I suspect, is charge management which is much more complex in a modern car than “just set the alternator at 14.4V and let the battery take what it wants”.

So, the car’s software needs to know capacity, chemistry and age to manage the charging process.

I think one of my OBD tools can set the right variables, but you have to know what they all are - there isn’t a single “new battery” setting, but some of the after-market tools can “re-code” for a new battery with a nice user interface.

Fully (probably nearly maybe) charged and all seems ok now- turns out she had both heated seats on full all day yesterday. I’ll have to keep an eye on it.