[trainwreck]

Does anyone know where the blower motor relays K61 and K62 are located? I found a pic but it is so vague they may as well be under the car!

I appreciate the help!

 

[colin25]

Here you are. What is the problem with the blower motor, total failure of motor due to relays or fuse failure, or the more common fault on the 451 of blower motor not working, then go over a bump or pothole and motor starts up again. If the latter I have your solution and its not the relays but the motor that is at fault. More info to follow if its the latter problem.

 

[1stiski]

Our 09 451 just had the same issue , but not even a bump would get it moving enough . Did the easy remove of the blower, cleaned the contact area where the brushes rub and it’s now perfect again . All speeds and doesn’t require the foot or road bump to get it going .

 

[colin25]

Well may as well enlarge on 1stiski's answer

The common problem on the 451 is that the blower motor is cheap, and the commutator ring of the motor gets covered with black carbon, so you get 'dead spots'. Usually bumps or potholes get it going again for a day or two. As 1stiski says remove motor, clean the commutator with some emery paper or part of a emery foam block, and replace. This solution usually lasts two years, then you have to do it again.

 

[1stiski]

^^^^ and it’s so easy !! Release the wire plug , twist the whole motor counterclockwise and it pops out ! Wow , how much did Mercedes clobber customers on this one .

 

[trainwreck]

Here you are. What is the problem with the blower motor, total failure of motor due to relays or fuse failure, or the more common fault on the 451 of blower motor not working, then go over a bump or pothole and motor starts up again. If the latter I have your solution and its not the relays but the motor that is at fault. More info to follow if its the latter problem.

Blower motor, resistor, evap sensor and dash controls are all good. I want to test the relays. I have seen that picture but I can't tell where that is located under the dash.

Thank you for replying