No air flow from vents

L79racer

Original poster
Member
Apr 26, 2012
13
I had a dead battery so I bought new battery. Now I dont get any air flow out of the dash vents. Do I have to re calibrate the actuators, if so, how do I do it? Thanks in advance.
 

RayVoy

Member
Nov 20, 2011
939
It happened because you disconnected the battery, the cure is to disconnect the battery.

Actually, a reboot. The actuators are self-aligning; but need to be forced into the procedure.

Sometimes, 2, or 3, disconnects are required to reset the actuators. If the 1st one doesn't work, re-position the controls and try again. Do not touch the controls for a couple of minutes after the reconnect.
 

L79racer

Original poster
Member
Apr 26, 2012
13
RayVoy said:
It happened because you disconnected the battery, the cure is to disconnect the battery.

Actually, a reboot. The actuators are self-aligning; but need to be forced into the procedure.

Sometimes, 2, or 3, disconnects are required to reset the actuators. If the 1st one doesn't work, re-position the controls and try again. Do not touch the controls for a couple of minutes after the reconnect.

Thanks, will give it a try tomorrow.
 

The_Roadie

Lifetime VIP Donor
Member
Nov 19, 2011
9,957
Portland, OR
1) You actually have to turn the ignition on (don't have to start the engine) after the battery reconnection, to trigger the recalibration process.

2) The airflow mode actuator could have died, and sometimes the recalibration process doesn't get it back.

There are dozens of threads on the subject of "dash vents quit working" and "airflow mode actuator replacement". Including this: http://gmtnation.com/f23/2002-envoy-mode-door-actuator-replacement-2787/
 

L79racer

Original poster
Member
Apr 26, 2012
13
I finally got around to trying to fix the actuator. It seems to be bad. I removed it and played with it. I plugged the connector back in and let it hang while I tried to operate it. It always want to go back to the floor position and does not go back the other way to the vent position. I'm wondering if its the control switch. Even if the control is set for the vents, as soon as I connect the actuator it moves to the floor position. I think that there should be no power to move the actuator to floor position without the control switch telling it to. Any thoughts??
 

The_Roadie

Lifetime VIP Donor
Member
Nov 19, 2011
9,957
Portland, OR
Actuators also contain a position feedback sensor. The sensor could be bad, or the wiring to the control module, or the control module itself. Need to check the voltage on all pins of the actuator and compare it to the other side equivalent, or put in a new actuator, to troubleshoot it definitively.
 

L79racer

Original poster
Member
Apr 26, 2012
13
the roadie said:
Actuators also contain a position feedback sensor. The sensor could be bad, or the wiring to the control module, or the control module itself. Need to check the voltage on all pins of the actuator and compare it to the other side equivalent, or put in a new actuator, to troubleshoot it definitively.

Ordered new actuator last night. $40 with shipping included from Rockauto.
 

L79racer

Original poster
Member
Apr 26, 2012
13
Its all fixed. It was a bad actuator. Here is what I found. Once you remove the actuator the trap door will fall down to the vent position. When I received the actuator it was in the floor position. You can not install it like that. There is no way to hold the door in the correct position to get it to work You must open the actuator up, lift the small motor off the gear so you can rotate the white arm into the correct position. Do not twist the white arm with out opening it up as you will strip the gears. Then I removed the white arm and installed it into its correct place and made sure it moved the door from vent to floor smoothly and fully. You will hear the door hit both stops . Then I installed the actuator onto it. Here is a picture of how it should look. You can see the two notches in the metal sleeve are rotated to the left just past of the straight up and down lines on the black case. I did not have to remove any triangle bracket like another post said. I removed the black plastic from bottom of dash. Then the plastic just below the steering wheel and removed the metal support behind that. I also moved the duct out of the way. If you lay on your back you can look up and see the actuator. Hope this helps.

bz9l2.jpg
 

meerschm

Member
Aug 26, 2012
1,079
You were lucky and had the actuator which is the easiest one to get to.

glad it did the trick.

:tongue:
 

Forum Statistics

Threads
23,392
Posts
638,780
Members
18,601
Latest member
Chris Moore

Members Online

No members online now.