[rollin155]

Hey everyone, I realize a/c heat has been a topic for years now, I must say unsuccessful on finding a direct solution. recently I was out driving with my son that is autistic and he had a stressful moment in the car everything has to be set right, while doing so pressed repeatedly all control functions a/c heat fan level etc for several minutes. Then the snap shot light came on. When that was in passing an all was well for him, the next time I was alone adjusting the temperature I noticed there is no air flow to defrost or floor, only through front vents. the a/c works fine but no heat from any location, also no air flow through seats either way that I could feel. The rear passenger seat console vents seems cold to me. I was getting ready to replace all 3 units in dash, just wanted to get opinion in case there is something else I can do or another way I can save money an time. I replaced the easy fan blower, the fuse test, then had a technician recharged freon he fixed leaking a/c line to. thank you for providing links for ac delco.

code feature that are current:

B 0179: out put air temperature sensor #2 (lower single or lh) circuit range performance.

B 0248: mode door inoperative error

B 0268: a/1 door inoperative error

B 0408: temperature control #1 main/front circuit malfunction.

B 0423: Air is door #2 inoperative error

B 0428: Air mix door #3 inoperative error

B 0515: rh heater discharge temperature sensor failure. I know it’s summer time but it will still need to be fixed sooner or later. Thanks for your guidance.

 

[basscatt]

HOPEFULLY - the system was simply overwhelmed by all of the commands at the same time -
try disconnecting BOTH battery cables and touch them together for a few seconds -
this acts as a re-boot - thus clearing the messed up memory of the various modules -

remember -
disconnect the NEGATIVE cable FIRST -
connect the POSITIVE cable FIRST -

 

[rollin155]

Hey thanks for the reply, I tried that but still the same. looks like I’m going in and under dash soon.

 

[rollin155]

hey thanks again basscatt, i should’ve checked with you first, read some of your other posts from years ago, found one similar to what im going through with hvac.

 

[rollin155]

Hey trying to narrow my path on the direction before I attempt to fix this. question how likely that 2 actuators to fail same time?

 

[sefiro]

A short or bad shared ground can take out multiple items at the same time.

 

[basscatt]

Hey trying to narrow my path on the direction before I attempt to fix this. question how likely that 2 actuators to fail same time?

======================
question how likely that 2 actuators to fail same time?
lets break this down - the easy stuff first -

the B0423 #2 - passenger side and B0428 #3 - back seat MIX DOORS
are controlled by one single actuator -
SO - THAT wouldn't be too difficult to understand -
HOWEVER - both of those codes are RARE -

faulty MODE door actuator - by itself - not an uncommon problem -

#1 driver side MIX door actuator - by itself - also not too uncommon -

B0268 is the - outside air - RECIRCULATE DOOR actuator -
can't remember EVER discussing a failed recirculate door -

and I have never heard of the duct temperature sensors failing -

NOPE - way too many things went bad at the same time -
THIS DOES NOT MAKE SENSE -

UNLESS - as sefiro suggested - a ground or plug got disturbed -

there is a fairly major ground lug "hidden" behind the passenger side kick panel -
I would start looking there -

 

[rollin155]

I took it to a well known shop I’ve have done business with for years and ask if they could scan which they seemed promising, they told me later could not get any communication or recalibrate using it. he said possible control module or ask dealer. I know to many commands at once was overwhelming definitely created a over surge at some point. I can follow on what you mentioned first seems bout right.

 

[rollin155]

correct sefiro it was a power source connection. i know you can do many diy projects but l couldn’t locate my problem. i didn’t want to take to the dealership it was my last option. their tech tool is more in-depth showed all history codes from the past previous owners than the few ive seen since 2015. definitely pay more at the dealer diagnostic time than most. finding the right guys along the way with patience helps thank you for the details basscatt glad it’s over.