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Old 11-17-2010, 08:22 AM   #1
kikkegek
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Rear ventilation from two to multiple speed

hello,

the switch for the rear ventilation in my ride is broken. I need to replace it. I checked to see if the wires are still working. and they are. I measure an amperage of 1A at LO and 10A at HI setting.

But LO is too low and HI is too high. HI feels like a storm inside the car. I am now looking for a solution or new switch to make it possible to select speeds in between or at least a middle speed, so I can vent the rear of the car "normally".

any ideas?

and where can I find the controller for these two speeds right now?
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Old 11-17-2010, 08:35 AM   #2
motornut
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Re: Rear ventilation from two to multiple speed

the switch in the dash?
the speed/voltage/amps is not controlled by the switch
it's just a switch
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Last edited by motornut; 11-17-2010 at 08:36 AM.
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Old 11-17-2010, 09:01 AM   #3
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Re: Rear ventilation from two to multiple speed

Quote:
Originally Posted by motornut View Post
the switch in the dash?
the speed/voltage/amps is not controlled by the switch
it's just a switch
huh? so the fan in the back has a connection for LO and for HI speed?

In the LMC catalog a resistor is shown in the wiring.

but I have no clue (yet) on where this is inside the car?
and I dont know the specs of this resistor?

The way LO speed is made is either by deviding the current (voltage) in two using a resistor in parallel to the fan or by putting it in series with the fan, thereby deviding the available amperage (power?) in two...I am not sure about the last thing though.

can you help me with that?
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Old 11-17-2010, 10:15 AM   #4
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Re: Rear ventilation from two to multiple speed

yup hi and low
can't find a decent pic of the switch....on work puter
if i was home.......crap the burb an't there either lol
i tore it all out and my wires outa the 88 as the heater hoses started to leak
ac quit
wires coiled on the hump.......
the black had one switch/window/gate
one for fan
gold one had one for speed
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Last edited by motornut; 11-17-2010 at 10:26 AM.
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Old 11-17-2010, 10:25 AM   #5
motornut
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Re: Rear ventilation from two to multiple speed

but it's just a switch
i used mine for the dome light
up turns the light on
middle off but dial still works
down works with the doors
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Old 11-17-2010, 10:43 AM   #6
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Re: Rear ventilation from two to multiple speed

he thanks motornut (you gotta real name?)!

Here is what mine looked like before I took the bottom one out:


The top one has electrical and vacuum hose connections on the back, but does not seem to do a thing. I need to look into this.

The bottom one says REAR A/C and has LO (left) OFF (middle) and HI (right).
It has a 3 wire connection to the back of it and no vacuum connections.

Is yours identical?
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Old 11-17-2010, 11:55 AM   #7
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Re: Rear ventilation from two to multiple speed

As stated before, the switch is just a switch, it is merely opening or closing a current path. Is this an "aftermarket" add on or do all Subs have this. Maybe you can PM a mod and have this moved to the Sub-thread for Suburbans?
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Old 11-17-2010, 01:32 PM   #8
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Re: Rear ventilation from two to multiple speed

I had to replace a blower resistor assembly in my 03 Burban because it was only working on the two highest settings and not on low and mid.

Wonder if you could adapt one of these and a modern switch from a donor?

Do a google search for suburban heater blower a/c control module
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Old 11-17-2010, 03:55 PM   #9
motornut
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Re: Rear ventilation from two to multiple speed

hi its John
looks the same as yours
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Last edited by motornut; 11-17-2010 at 03:57 PM. Reason: haha forgot my name
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