Heater Fan Not Running

[E55BOF]

Good day everyone.

The car is a 2014 SLK 55 on 58K miles. The heater blower motor is not running at all; it was working fine when I switched off yesterday, today there's nothing. The iCarsoft checking the blower motor alternates between displaying 14.60 and 0 volts - nothing in between - and 'MOTOR RUNNING' and 'MOTOR NOT RUNNING' messages.

There's a dribble of warm air coming through the fascia vents at motorway speeds, so it's not a flap problem. Anybody think it's anything other than a resistor pack issue, and if so, what?

 

[Dodipops]

Blower motor itself??

Give it a bang with your hand and if it comes on it’s more likely the motor than the resistor.

 

[Bellow]

When I had the resistor pack fail on my smart, the blower worked at full speed setting but not any other. Full speed setting kind of bypasses the resistive element. Resistor pack failure was commonplace on fortwos and the symptoms were always exactly as above.

 

[E55BOF]

No blower at any speed. Terry Gates' advice is to replace both motor and resistor pack; the problem usually starts in the motor, which takes out the resistor pack, and if only the pack is replaced, the fault could, and will, recur at any time. I thought about a used one from a low-mileage car, but thought better of it; you only have the breaker's word that the donor car is low-mileage...

The motors are on back order at the factory, but I've ordered one (new & genuine) from a supplier in Lithuania, and the resistor packs are available here at the moment, so he's got one on the shelf awaiting the arrival of the motor.

 

[optimusprime]

Checked fuses ?

 

[E55BOF]

Blower motor itself??

Give it a bang with your hand and if it comes on it’s more likely the motor than the resistor.

Well, I'll be blowed... literally. I removed the battery cover, reached in and spun the blower impeller by hand, and B****r Me! It's working again.

It will go again, of course; if it was fully serviceable, it wouldn't have stopped in the first place. I'll keep the spare motor and resistor pack for when it does go again, and I can't get it running, but in the meantime, Happy Days...