Blower ground location
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Blower ground location
I tested my blower resistor with a multimeter im getting 0v on ground, 12v on positive, anyone know the location for the ground location for the blower, i already installed new blower and resistor , blower fuse and climate control are good, still no air flow ,
Out Of Control!!
Joined: Apr 2019
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From: Silicon Valley
W212 MY'14 M276-3.5NA @75kMi
Fan gets + 12V and pulses of GND.
Unlikely solid GND and pulses of +12V
Can you help explain your test results ?
You're saying :
fan is getting 0V/+12V
but no air flow
This being a new fan, it should definitely spin given these conditions are true.
Something is not adding up here.
Last edited by CaliBenzDriver; Mar 13, 2026 at 04:47 PM.
Out Of Control!!
Joined: Apr 2019
Posts: 12,002
Likes: 6,827
From: Silicon Valley
W212 MY'14 M276-3.5NA @75kMi
FOOTWELL GND POSTS
The blower GND source is 90% likely the nearby footwell GND post.
Cleaning painted posts requires DISCONNECTING Main/Aux batteries + scanner skills to clear faults else boatloads of faults.
Cleaning painted posts requires DISCONNECTING Main/Aux batteries + scanner skills to clear faults else boatloads of faults.
Last edited by CaliBenzDriver; Mar 14, 2026 at 02:08 PM.
Thread Starter
Junior Member
Joined: Nov 2025
Posts: 25
Likes: 0
The answer is GND likely managed by the ballast - The mystery box is not a resistor.
Fan gets + 12V and pulses of GND.
Unlikely solid GND and pulses of +12V
Can you help explain your test results ?
You're saying :
fan is getting 0V/+12V
but no air flow
This being a new fan, it should definitely spin given these conditions are true.
Something is not adding up here.
Fan gets + 12V and pulses of GND.
Unlikely solid GND and pulses of +12V
Can you help explain your test results ?
You're saying :
fan is getting 0V/+12V
but no air flow
This being a new fan, it should definitely spin given these conditions are true.
Something is not adding up here.
Out Of Control!!
Joined: Apr 2019
Posts: 12,002
Likes: 6,827
From: Silicon Valley
W212 MY'14 M276-3.5NA @75kMi
Not the blower motor itself, its not blower connector that comes out of the vehicle, when i probe it, it shows 12v for on postive red cable, and 0v on ground cable, im sure the new fan is okay, Im pretty sure the blower ground location point is loose or fell off, i just cant locate it, at this point im getting annoyed i might sell the vehicle as is lol
