Hi everyone,

I have a 2012 L322 and the front heated seats aren’t working. Both the driver’s and passenger’s side heated seats don’t warm up, while the rear ones do. I plugged it in a while ago on my Autel diagnostics, and it came up with fault code B1231-7A. Please refer to the vehicle service manual.

When I turn on the heated seat, the temperature shoots up really quickly and then cuts out (without the seat actually warming up). I can hear the fan kick in when it’s turned on, so there’s power getting there.

Does the heated seat use the car’s normal heating system? Because that doesn’t work either due to an unknown fault that I’ve given up on finding.

The cooled function fan kicks on makes a little difference but nothing to much, is this supposed to work from the cars aircon?

The aircon also doesn’t work because of a leak somewhere, so the car is only nice to drive when the weather is exactly right.