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 no defrost, no floor vent, only middle vents working

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benn

benn


Posts : 557
Join date : 2011-12-22
Location : Ontario, Canada

no defrost, no floor vent, only middle vents working Empty
PostSubject: no defrost, no floor vent, only middle vents working   no defrost, no floor vent, only middle vents working Icon_minitimeSat Apr 20, 2013 10:16 am

my '95 RMW only blows heat out of the middle vents, no matter what setting the climate control is on. i NEED defrost to work in order to get it past a safety test and drive it. any ideas?


my AC doesnt work.
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benn

benn


Posts : 557
Join date : 2011-12-22
Location : Ontario, Canada

no defrost, no floor vent, only middle vents working Empty
PostSubject: Re: no defrost, no floor vent, only middle vents working   no defrost, no floor vent, only middle vents working Icon_minitimeSat Apr 20, 2013 10:40 am

Blend door??
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silverfox103
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silverfox103


Posts : 3344
Join date : 2008-11-05
Age : 75
Location : Littleton, NH & St. Simons, GA

no defrost, no floor vent, only middle vents working Empty
PostSubject: Re: no defrost, no floor vent, only middle vents working   no defrost, no floor vent, only middle vents working Icon_minitimeSat Apr 20, 2013 11:34 am

Never had this problem with the wagons, but I did with my Mercury Grand Marquis. I had to have the control unit repaired (or replaced).

Whatever it's worth

Tom
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jayoldschool

jayoldschool


Posts : 2728
Join date : 2009-06-14

no defrost, no floor vent, only middle vents working Empty
PostSubject: Re: no defrost, no floor vent, only middle vents working   no defrost, no floor vent, only middle vents working Icon_minitimeSat Apr 20, 2013 12:58 pm

Wow, I have never heard of anyone checking defrost on a safety.

Take your home plate off. Towards the rear of the intake, on the side, are two vacuum connections. The bottom one is for the fuel pressure regulator. The top one is the one that provides vacuum to the HVAC control head. Make sure that is connected. Check the plastic hose to make sure it isn't broken. Check under the dash to confirm that the other end of the hose is connected and is providing vacuum. On my SS, the vacuum line melted on my header. The hose is in the wiring bundle that is held in place by the bracket on the trans dipstick tube. With a T56, I didn't have that bracket, and the bundle dropped onto the header. However, I believe the system defaults to defrost with no vacuum. This is on the Caprice/Impala SS manual HVAC, though. Hopefully the RM is different. If it's the same, and you find everything connected, you can probably get the system to default to defrost by simply disconnecting that hose.

no defrost, no floor vent, only middle vents working Ci259
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benn

benn


Posts : 557
Join date : 2011-12-22
Location : Ontario, Canada

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PostSubject: Re: no defrost, no floor vent, only middle vents working   no defrost, no floor vent, only middle vents working Icon_minitimeSat Apr 20, 2013 3:50 pm

jayoldschool wrote:
Wow, I have never heard of anyone checking defrost on a safety.

Take your home plate off. Towards the rear of the intake, on the side, are two vacuum connections. The bottom one is for the fuel pressure regulator. The top one is the one that provides vacuum to the HVAC control head. Make sure that is connected. Check the plastic hose to make sure it isn't broken. Check under the dash to confirm that the other end of the hose is connected and is providing vacuum. On my SS, the vacuum line melted on my header. The hose is in the wiring bundle that is held in place by the bracket on the trans dipstick tube. With a T56, I didn't have that bracket, and the bundle dropped onto the header. However, I believe the system defaults to defrost with no vacuum. This is on the Caprice/Impala SS manual HVAC, though. Hopefully the RM is different. If it's the same, and you find everything connected, you can probably get the system to default to defrost by simply disconnecting that hose.

thanks man!! i did the homeplate delete when i first got, i may have knocked off a hose.
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jayoldschool

jayoldschool


Posts : 2728
Join date : 2009-06-14

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PostSubject: Re: no defrost, no floor vent, only middle vents working   no defrost, no floor vent, only middle vents working Icon_minitimeSat Apr 20, 2013 5:42 pm

Keep us posted, good luck!
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benn

benn


Posts : 557
Join date : 2011-12-22
Location : Ontario, Canada

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PostSubject: Re: no defrost, no floor vent, only middle vents working   no defrost, no floor vent, only middle vents working Icon_minitimeMon Apr 29, 2013 3:23 pm

FIXED! cheers

thanks again jay! it was a vacuum line you posted a pic of. mine didnt fall off at the elbow like the pic, but further up where where it goes into that main wiring harness loom. there was a rubber hose connection there where it had seperated.

almost ready for safety.

rear ebrake cables and a floor patch to go. so far ive done everything myself. feels good. Smile
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jayoldschool

jayoldschool


Posts : 2728
Join date : 2009-06-14

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PostSubject: Re: no defrost, no floor vent, only middle vents working   no defrost, no floor vent, only middle vents working Icon_minitimeMon Apr 29, 2013 4:08 pm

Glad to help.
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andrewchayes1




Posts : 6
Join date : 2018-12-05

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PostSubject: Re: no defrost, no floor vent, only middle vents working   no defrost, no floor vent, only middle vents working Icon_minitimeSat May 18, 2019 12:24 am

Just wanted to say I just had the same problem with my 96 RMW and this cured it. Thank you!!!!
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PostSubject: Re: no defrost, no floor vent, only middle vents working   no defrost, no floor vent, only middle vents working Icon_minitime

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