04 Suburban auto climate control issue

[wardriver]

I have a 2004 Suburban 8.1 liter.

Intermittant ac issues.

Room temp. (outside air temp) will blow from vents. When I shut truck off and then re-start its fine and blows wonderfully cold air.

This has happened about 4 times in the last week. Each time if I shut her off and re-start its fine.

Mine has the automatic digital control. No weird sounds from compressor.

I believe its the #1572956 acdelco AC/heat control unit. ($145 from Rocks)

Am I right?

If so does anyone have a pdf that shows info. for replacement

[MT-2500]

Originally Posted by wardriver

I have a 2004 Suburban 8.1 liter.

Intermittant ac issues.

Room temp. (outside air temp) will blow from vents. When I shut truck off and then re-start its fine and blows wonderfully cold air.

This has happened about 4 times in the last week. Each time if I shut her off and re-start its fine.

Mine has the automatic digital control. No weird sounds from compressor.

I believe its the #1572956 acdelco AC/heat control unit. ($145 from Rocks)

Am I right?


Try a reset on it.
Disconnect the RDO/bat fuse for 3 minutes and hook it back up and let us know what it does.
If so does anyone have a pdf that shows info. for replacement

Try a reset on it.
Disconnect the RDO/bat fuse for 3 minutes and hook it back up and let us know what it does.

[wardriver]

I can try that.

Based on the info. given do you believe it to be the climate control unit?

[MT-2500]

Originally Posted by wardriver

I can try that.

Based on the info. given do you believe it to be the climate control unit?

Needs proper testing to find out.

[wardriver]

Pulled fuse as directed.

Ac still works intermittantly, when shut off then back on it is fine.

[MT-2500]

Originally Posted by wardriver

Pulled fuse as directed.

Ac still works intermittantly, when shut off then back on it is fine.

The Havc is computer controlled
Unless you just want to throw parts at it the first step in checking it out is to get it on a Havc capable scanner and get codes and read out on what is going on when it is acting up.
Intermittent acting up can be wiring or connection problem.
Any recent electrical problem or repairs?
Post back any codes.

[wardriver]

No recent repairs or bunnies chewing on wires.

I did find a post at another site where same symptoms and the hvac module was to blame, replacing fixed it.

Plenty of actuator posts but very few on this.

Seems like the arrows are point to hvac module. I dont want to spend $90 for a dealer to tell me he cant duplicate the issue or find a code, one dealer wanted to add freon, knuckle head idea if you ask me.

I will order the ac delco part from rocks, I'll report back with my end result.

[MT-2500]

Originally Posted by wardriver

No recent repairs or bunnies chewing on wires.

I did find a post at another site where same symptoms and the hvac module was to blame, replacing fixed it.

Plenty of actuator posts but very few on this.

Seems like the arrows are point to hvac module. I dont want to spend $90 for a dealer to tell me he cant duplicate the issue or find a code, one dealer wanted to add freon, knuckle head idea if you ask me.

I will order the ac delco part from rocks, I'll report back with my end result.

That dealer may not be so dump.
That could even be your problem.

Let us know how throwing parts at it goes.

[wardriver]

Your a true comedian.

1.) From my experience low freon equals warmer air, my 99 blew semi cold air, I checked it and voila it was low and adding fixed it.

2.) I spoken to 3 Gm mechanics who said "no, freon not an issue with that."

I'm sorry you have no idea on what to do, but instead of racking up posts for the sake of numbers and trying to be mean spirited perhaps bow out if you don't know.

I have solved lots of issues here with the fantastic posts of many and I'm very grateful for that.

I'll be sure to report back.

[MT-2500]

Originally Posted by wardriver

Your a true comedian.

1.) From my experience low freon equals warmer air, my 99 blew semi cold air, I checked it and voila it was low and adding fixed it.

2.) I spoken to 3 Gm mechanics who said "no, freon not an issue with that."

I'm sorry you have no idea on what to do, but instead of racking up posts for the sake of numbers and trying to be mean spirited perhaps bow out if you don't know.

I have solved lots of issues here with the fantastic posts of many and I'm very grateful for that.

I'll be sure to report back.

There is no way anyone can help you if you already know it all.
And we we can not help you if you do not do the proper testing and give proper information.
Good luck

[wardriver]

Im sorry if I hurt your feelings.

I dont have access to hvac testing equip as I dont have the $$$$ to go to dealer, I have successfully repaired many of things with the help of this forum.

Not everyone can get the codes.

Sorry.

[j cAT]

Originally Posted by wardriver

Im sorry if I hurt your feelings.

I dont have access to hvac testing equip as I dont have the $$$$ to go to dealer, I have successfully repaired many of things with the help of this forum.

Not everyone can get the codes.

Sorry.

hook up a cheapo ac recharge guage. what are the pressures when this works and does not work . you got 30.00 .

you must take troubleshooting steps to determine this intermittent cause . since intermitent it is gonna be hard. might have to replace some good parts to get at the bad part. ya the ac computer module could be bad / also could be a switch and a lot of other things. the dealership could just replace all the items and send you the bill for alot of unnecessary work/parts.

must also have a meter volts / ohms ..as the testing comes in we will move on, to narrow down the varmit causing this..

this is not a simple one answer issue.........

[wardriver]

I will check the pressures and report back.

Thank you jcat!

[MT-2500]

Originally Posted by wardriver

Im sorry if I hurt your feelings.

I dont have access to hvac testing equip as I dont have the $$$$ to go to dealer, I have successfully repaired many of things with the help of this forum.

Not everyone can get the codes.

Sorry.

No problem on hurt feelings.
You are the one with a problem of not taking our advice.
Rule no one if auto AC controls are not working right.
And As one dealer has told you and I tried to tell you and now J cat is telling you check the charge.
Give us your high and low pressure readings at idle and at 2K rpm with compressor running.
Good luck

[wardriver]

Ill check them.

Thanks