2012 E350 Coupe MAF/IAT fault.

[Waggy2000]

Engine management light is on.
OBDII reader shows P0111 fault code and message; ECU reporting IAT sensor reading out of normal range.
Is the IAT sensor/s part of the MAF sensor/s or are they separate units further up the intake ducts?
Any useful information would be appreciated.

 

[Uncle Benz]

They are part of the air mass sensor. Have you replaced the batwing air mass sensor assembly recently? I only ask because the cheap ones on eBay have bad temperature sensors in them. I’ve seen three or four with this problem

 

[Waggy2000]

They are part of the air mass sensor. Have you replaced the batwing air mass sensor assembly recently? I only ask because the cheap ones on eBay have bad temperature sensors in them. I’ve seen three or four with this problem

Thanks for the reply Uncle Benz.

I bought a Bosch one, but just one as they’re £180 each.
I hoped only one had failed out of the two and tested both sides. The MAF fault went but the IAT fault persisted.
Today I unplugged them both, ran a diagnostic, cleared the fault, turned off the ignition, plugged them back in and ran the car on the drive for a bit and the fault hasn’t shown back up and the intake temperature was showing normal on the sensor reading.
I’ll check it again once run properly though a heat & cool cycle.

I mainly wanted to check there isn’t another IAT sensor that I would need to be mindful of.

I’ll post on progress.