So, 99, auto HVAC. Right blend door was throwing out of range errors...

Pulled the dash & swapped the right side with an aftermarket new actuator. Codes went away... but figured while I'm at it, lets just change the left/drivers too & be done with it.

New aftermarket in the left immediately throws out of range error.... stuff the old one back in... you guessed it, even with a reset via fuse 27, same thing with the old one too?!?

Took a few days but got anther/diff brand actuator (NOT GM still). Toss it in, reset. All looks good, no errors, several ignition cycles & tests all pass. Unhook the battery overnight as we are dealing w/ a seat position sensor error as well that will cause random seat movement overnight & kill the battery.

Next morning, power back up & test ac... 2nd new actuator is now also throwing out of range & position short to ground (B0441 & B0361). WTH!!!! Reset worked once but now it just sets the codes again right away. So, 2 different actuators which aftermarket usually allow for more door movement without the range error?!? I'm about to try swapping out the control head but I'm open to ideas/input.

And please, lets not got down the 134a being low, I checked & its fine. Also, when it did work the few times, ice cold both sides, passenger adjust warms up a few degrees if selected etc.

TIA!

 

Just an update, another new actuator (3 now)... same thing, works okay a couple times then starts failing w/ the 441 & 361 errors... So, I swapped the control head w/ another known working unit. No change... btw, I did follow the service manual procedure to check for 5 volt range on 2 wires at the actuator & then check for continuity from control head plug to actuator plugs & for shorts to ground. All test fine & FSM say replace actuator is the next step.... obviously still failing.

It appears the error occurs on the cold side run of the actuator, so I've pulled the cover on one & indexed the feedback gear 1 tooth to allow more movement (all the way to the mechanical stop) on that side. (tested w/ ohm meter). About to swap it back in again.

 

final update.... my last change to the actuator to allow more travel to full cold resolved it... BTW.... the direction is opposite for driver/passenger side units. It appears the learn process doesn't have an issue w/ pushing to hot, its the cold side of the door swing that tends to go too far as the internal door seals wear out.

 

Interesting. So probably all you needed was to re-index the original actuator.

 

You changed both hvac actuators? Did you remove the dash or replace them from underneath?I still need to do this.

 

have you replaced both actuators? What brand did you go with or find out was best the dorman replacements they use on the 2000+ trucks are the same i think. Im trying to replace both of mine and wonder if it can be done without removing the whole dash.

both mine left and right have the out of range and short to ground all 4 codes common with the actuators think the gears are cracked and not switching from hot to cold. Would like to know if its possible to replace BOTH from the underneath or if you have to remove the console, hvac, radio or anything or just the bottom dash covers.


I see you pulled the dash to replace them? You swapped a few of them in did you pull the dash everytime?

 

Right side I have NOT found a way to replace without pulling dash. But I only replaced it the one time. The left was the one I had to swap over & over. Dash though, If you know all the screws, its really not that big a deal. Maybe 2 hours taking your time. FSM is the key to all the screws & the glove box. Don't forget the one on the far right side down at glove box level.

Actuators only use 2 screws & post to align the position.. You can access the right side screws w/ a nut driver & 7/32 socket if I remember right. Don't drop the screws, can be a bitch to find... Left side, is easy after removing the hush panel above the pedals, and the Bose box.

The last actuators I used were cheapo amazon china no name. In the past, I've used dorman, I've used Orielly Murray... Anymore, I think all of them will likely require a re-index based on your door swing... as long as the factory one doesn't have a broken gear, might even reuse them. They seem to have less available "over run" than most of the after markets.

 

So the passenger side requires dash removal and the drivers side can be done from underneath with the lower dash cover removed small ratchet 7mm or 5.5mm whatever it is? 7/32"? Mine just blows normal air not hot or cold so its not stuck in the heater core position. Is it possible for the blend doors to be stuck in the ac position i havent wasted putting freon in the system as i cant even get the doors to turn to heat and will the hvac doors not function without freon or correct reading from the ac pressure switch? Ive tried pulling the 27 fuse and resetting or indexing them didnt hear any gears turning. As far as i know even without freon the heater system should still function leading me to believe its bad actuators as i have all 4 codes for them out of range, short to ground or whichever sequential codes.

Just remove the console both radio, hvac head units, instrument cluster and all 10+ dash screws?

 

HVAC & radio heads do NOT need to come out. Just the surround in order to access a few screws holding the dash pad around that area. Doors should index with fuse 27, or battery disconnect. Try turning the key to on (no start), that is when things come to life..

Get an FSM, even if its a few years off in the C5 range, most of this stuff in the same.