E70C32 - AC-LIN: Heating in third row of seats is not responding

[ptr727]

2016 X5 50i.
After I got a battery drain warning I read codes using BimmerLink, and other than expected "213601: Power management: Quiescent current violation" and "8040BD: Terminal 30F reset or shutdown", I also got "E70C32 - AC-LIN: Heating in third row of seats is not responding".

I found a TSBS for this: https://static.nhtsa.gov/odi/tsbs/20...47261-9999.pdf

I'm obviously way past warranty, but do still have extended platinum warranty, wondering if BMW will charge me to fix this (in which case I'll pass), or is it something they will cover at their own cost?

[RED_Y_]

I would expect your extended warranty to cover such thing.

[suitedcboy]

Yes, but do not say you found the code. Tell them the third row was not heating a few times when that seat was used. BTW, does the third row seat heater feature work?
There is a chance that they find something has damaged the cable back there and a wiring physical wiring repair may not have coverage. No accusations here but a person (little person) that drags a toy out of a place around seat and disconnects a connector or pulls a wire out of harness is not a warranty thing, it is damage like cutting a seat with something you place on seat. LIN (local interconnect network) signal response could be open wire or power supply interrupted to the seat heater module. I am unsure of the way BMW does it on that model but on most makes these days the seat heat uses what looks like a relay but is a module that powers on heater element and then extrapolates temperature of seat heater elements. The command to operate is over a LIN protocol wire to that module and the module in turn responds with the temp or a fault response. The code as you posted would be for no communication from that module. LIN uses a few modules all sharing one comm wire with each module having an ID. HVAC would be the commander and know when a commanded module does not respond to the command.

[Qsilver7]

Interesting...I would first assume that those codes were caused by the discharged battery. Has the OP cleared the codes since taking care of the discharged battery to see if those 3 codes come back? If they don't/didn't...then the new battery or charged battery probably took care of the problem?

[ptr727]

Dropped car off this morning at dealer to have both batteries replaced. Yes, I could have done it myself with non-OEM batteries and BimmerLink for about $600, dealer quoted $1070, acceptable.

Service advisor smart enough to not mention anything about codes, just state symptom, and state fix if warranty coverage.

I did test the 3rd row vent this morning, does not work, so code is probably accurate and not related to low battery.