N29/2 rear booster blower controller.
My rear booster blower has taken on a life of its own! It blows air when switched off, I've had to pull the fuse to disable it.
Many thanks.
The N29/2 is located at the rear of the center console. It is controlled by the AAC Control Module.
Key out of ign. and with a test light or DVOM, check both contacts at fuse #10 for 12v; also check fuse #12 for 12v.
. Post back with results.
Last edited by Maj. Dundee; May 3, 2018 at 08:07 AM.
The booster blower controller, sits on top of the unit and is accessed by removing the centre cup holders. It's a solid state unit with an integral heat sink.
There's not much I could do except check the wiring, as best I could. I may price up a replacement, although, I don't sit in the back so I may leave it if it's expensive!
Thanks again for your help MD.
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I've had the radio and glove box off today, to check the wiring looms. I can't find anything amiss.
I was wondering if a relay controls this booster blower? I didn't get a wiring diagram with the vehicle. Anyone got an idea where to get a vehicle specific one?

The thing works correctly, all the functions are as normal. It just continues to run when you remove the key and lock up. Weird!
Fingers crossed MD can find something in his vast libraries!
Yes, I've found a code....
9607 Booster blower : There is a short circuit to ground or the line for the readback voltage has an open circuit. DTC Status : Current and stored.
Thanks MD.

2. That is a generic code, not a Mercedes code. You need to read the computer with Star Diagnostics system or a scanner that understands Mercedes codes and can query all subsystems, .
I got one, made from chinesium, from a seller on Amazon, cost was about $25 posted. I was expecting it to come on a slow boat but I got it within a week.
It seems that quite a few merc's have this resistor. Which is all that it is, a PWM Generator on the earth to the motor.


