Blower motor - how to distinguish positive/negative terminals?
#1
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Blower motor - how to distinguish positive/negative terminals?
My blower motor from my 2000 C2 cab failed, while I got a replacement, I realised my original blower motor was from older year parts. The problem is that older motor has a wider plug (lower) and the post-2000 motor has a smaller plug (upper).
I had to buy a plug again (below) and now my question is: How do I determine where should the positive wire goes to? Both the original wires are black and I couldn't tell which is which. Or, does it make any difference at all? Hope someone could help. Thanks a million.
#2
Trial and error is fine; you won't hurt anything. If you connect the wires backwards the motor will just spin the wrong way, and then you'll know you need to reverse the wires. Just hook it up temporarily with bare wires before making your final crimp/solder connections.
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Trial and error is fine; you won't hurt anything. If you connect the wires backwards the motor will just spin the wrong way, and then you'll know you need to reverse the wires. Just hook it up temporarily with bare wires before making your final crimp/solder connections.
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If you are going to bench test the wiring connection, make darn sure you enable the fan to spin freely. I could just see connecting the wires while it is sitting on the bench and having that thing go flying!
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#6
Since these are consider "purge" fans, wouldn't the air need to be blowing up and out of the engine compartment? Therefore, a simple polarity check of the fan using 12V +/- would determine the correct fan rotation and thus, point to the correct terminals?
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#8
Hi. Not trying to be contentious, but why would it be called a "purge fan" if it's pulling air into the engine compartment? This is not a radiator fan, right? I thought the premise behind the purge fan is that it serves to "delete" or "purge" hot air. Seems like I remember the manual saying that as well. Thanks for correcting me. I have a lot to learn.
#9
Nordschleife Master
Is this the rear spoiler blower? The plug should be labled "a-b" or similar. Post your current wire colors and ill see if there is a difference.
In the bentley book:
For 2002 and 2004 it shows b- rd/bk, a- bn
For 1999 its the same but b- br, i think both r considred brown
b is power from the relay, a is ground.
u will need to get the magnifier out and fing the lable on the connectors
In the bentley book:
For 2002 and 2004 it shows b- rd/bk, a- bn
For 1999 its the same but b- br, i think both r considred brown
b is power from the relay, a is ground.
u will need to get the magnifier out and fing the lable on the connectors
#11
Nordschleife Master
Ok ill try to remember to look up the hvac blower when i get home tonight.
#12
Nordschleife Master
So that plug in 99 should be labled 1 and 2, 1 is power from the blower resister and 2 goes to ground.
2002 and 2004 both show a 4 wire plug if im reading the book correctly
i would find the number labels on the 2 plugs and wire them the same.
2002 and 2004 both show a 4 wire plug if im reading the book correctly
i would find the number labels on the 2 plugs and wire them the same.
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I also took out the passenger airbag to make room for me to fix the front speakers that dropped out from the mount, rerun the wires and it now looks very neat.
Last edited by snoopybee; 08-19-2018 at 06:28 AM.