HVAC blower / Front winder defogger - same motors?
#1
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HVAC blower / Front winder defogger - same motors?
My HVAC blower stopped yesterday, but the blower for the front windscreen defogger/defroster still works with the HVAC on the far-right setting. The blower stops on any other setting. Are they the same blowers? Just curious if I need to check the relay/fuse or start planning on a bigger repair.
#2
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They are one and the same. That it still works in DEF mode suggests you have the all too common resistor pack failure.
Read up on many other posts on resistor pack replacement.
Alan
Read up on many other posts on resistor pack replacement.
Alan
#4
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My blower works only on the defrost position (no operation at all on any blower speeds when not in defrost mode) so I'm hoping it's just the relay. I'll swap 'em out this evening.
Anyone know if this is a common relay that can be found at a store carrying import parts?
#5
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Dave--
It's not a relay, it's a resistor pack that lives in the air duct downsteam of the motor, accessible under the hood.
There's also a chance that the wiring for the blower on the side of the HVAC controller was disturbed. Done any work in the dash/console lately? Otherwise, a bit of meter testing under the hood is in order. There are some good threads describing that so no need to retype it all.
My Big Suggestion on changing th resistor is to be sure to put a towel under the duct, so wehn you drop the screw that holds the resistor in place, it sits in the towel and not in the Big Black Hole below. Go head, ask why I recommend the towel. I dare ya!
It's not a relay, it's a resistor pack that lives in the air duct downsteam of the motor, accessible under the hood.
There's also a chance that the wiring for the blower on the side of the HVAC controller was disturbed. Done any work in the dash/console lately? Otherwise, a bit of meter testing under the hood is in order. There are some good threads describing that so no need to retype it all.
My Big Suggestion on changing th resistor is to be sure to put a towel under the duct, so wehn you drop the screw that holds the resistor in place, it sits in the towel and not in the Big Black Hole below. Go head, ask why I recommend the towel. I dare ya!
#6
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LOL Dr Bob,
I have pulled these on a few cars and have found one that is dead yet.
I did have that same issue with mine and it was a problem where power wasnt getting to a portion of it, I cleaned the connectors and it has been fine since.
I have pulled these on a few cars and have found one that is dead yet.
I did have that same issue with mine and it was a problem where power wasnt getting to a portion of it, I cleaned the connectors and it has been fine since.
#7
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Dave--
It's not a relay, it's a resistor pack that lives in the air duct downsteam of the motor, accessible under the hood.
There's also a chance that the wiring for the blower on the side of the HVAC controller was disturbed. Done any work in the dash/console lately? Otherwise, a bit of meter testing under the hood is in order. There are some good threads describing that so no need to retype it all.
My Big Suggestion on changing th resistor is to be sure to put a towel under the duct, so wehn you drop the screw that holds the resistor in place, it sits in the towel and not in the Big Black Hole below. Go head, ask why I recommend the towel. I dare ya!
It's not a relay, it's a resistor pack that lives in the air duct downsteam of the motor, accessible under the hood.
There's also a chance that the wiring for the blower on the side of the HVAC controller was disturbed. Done any work in the dash/console lately? Otherwise, a bit of meter testing under the hood is in order. There are some good threads describing that so no need to retype it all.
My Big Suggestion on changing th resistor is to be sure to put a towel under the duct, so wehn you drop the screw that holds the resistor in place, it sits in the towel and not in the Big Black Hole below. Go head, ask why I recommend the towel. I dare ya!
I haven't disturbed the wiring in the dash...ever. I put a new radio in the center console about 4 months ago. *shrug*
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#8
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Dave - yes if your switch does not activate the blower even on position 4 then its likely the fresh air blower relay.
It should probably really be called the HVAC relay since it switches more than just the blower.
Its a standard Bosch type SPST (SPDT types will also work fine).
Alan
It should probably really be called the HVAC relay since it switches more than just the blower.
Its a standard Bosch type SPST (SPDT types will also work fine).
Alan
#9
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So would a standard 40 amp 4 pin relay be fine? I don't know much about relays. Maybe I can pick one up on the way home from the local auto parts store....I know...I know....I'm being naive.
#10
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Dave, if it's the same as the Horn relay, I've got one you can have. Maybe you can swing by beofre you go home tonight. You can take the engine stand with you too!
#11
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#13
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Brian - probably not this time... which is good for Dave because a relay is both far easier to change and far cheaper!
Dave - yes any Bosch style 4 pin (SPST) relay will be fine - the 40A versions are much better than 20A or 30A versions for this - just typically better quality due to the better contacts...
Real Bosch (or Tyco now) relays are better quality than no brand versions...
Alan
Dave - yes any Bosch style 4 pin (SPST) relay will be fine - the 40A versions are much better than 20A or 30A versions for this - just typically better quality due to the better contacts...
Real Bosch (or Tyco now) relays are better quality than no brand versions...
Alan
#14
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UPDATE:
I replaced the relay with a new one and the blower worked at all speeds. Relay was an off-the-shelf version (Heffnauer brand or something like that).
HOWEVER, I stopped on the way home to use an ATM (5 minutes after installing the new relay) and when I started the car again, the blower stopped working. Same symptoms as before...no operating at settings 0-4, but normal blower when set on "defrost".
So, did I get a bum relay or do I have other issues to track down?
I replaced the relay with a new one and the blower worked at all speeds. Relay was an off-the-shelf version (Heffnauer brand or something like that).
HOWEVER, I stopped on the way home to use an ATM (5 minutes after installing the new relay) and when I started the car again, the blower stopped working. Same symptoms as before...no operating at settings 0-4, but normal blower when set on "defrost".
So, did I get a bum relay or do I have other issues to track down?