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02 defrost only

KenB1

New Member
Joined
May 23, 2006
Messages
1
02 AV 1500, HVAC system is always on defrost, no matter the control setting.

Watched some you-tube videos.  Tried a reset a couple times, no improvement.  Not sure if it's the right reset, point me to a thread if you know one.

Can rotate the actuator arm by hand, and will get air flow through all the right spots.

When I start the truck, the actuator defaults to defroster only.  I can move it by hand to the other settings, but if I let go it will go back to defrost.

Bad actuator, or perhaps a relay?  Can get an actuator for not too much $$, but don't want to throw money at it.

Tried a search, but little info on the 02.
 
:welcome: to the club  :wave:
Here is some info on the hvac system, link -->  HVAC 101



The HVAC control module will relearn the actuator limits whenever power is disconnected and re-connected to the module.

Use the following steps to perform the calibration update:

Turn OFF the ignition.
Remove the battery positive voltage circuit fuse of the HVAC Control Module.

Important: Failure to wait 60 seconds will not allow the HVAC control module sufficient time to clear the old calibration values.

Wait 60 seconds.
Install the fuse.
Turn ON the ignition.
Wait 60 seconds before.

 
 
I've read that as a safety feature , if something goes wrong with the actuator, that it will default to blow out the defrost vents, but mine didn't do that, it blows out of vents that blow in your face.  Any idea what the issue is?  I really want to get this fixed. thank you
 
could still be a bad actuator, or the air door is jammed/frozen.
 
KenB1 said:
02 AV 1500, HVAC system is always on defrost, no matter the control setting.

Watched some you-tube videos.  Tried a reset a couple times, no improvement.  Not sure if it's the right reset, point me to a thread if you know one.

Can rotate the actuator arm by hand, and will get air flow through all the right spots.

When I start the truck, the actuator defaults to defroster only.  I can move it by hand to the other settings, but if I let go it will go back to defrost.

Bad actuator, or perhaps a relay?  Can get an actuator for not too much $$, but don't want to throw money at it.

Tried a search, but little info on the 02.
For starters, read the HVAC codes with a capable scanner.  These don't turn on the SES light.
 
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