HVAC problem, vents in center console blow all the time

6MIKE60

MEMBER
2002 CHEVROLET SILVERADO
6.6L
V8
4WD
AUTOMATIC
59,800 MILES

VIN# 1GCHK23112F213262 a crew cab long bed truck LS trim, and captain chairs. The HVAC modes all work correctly with one exception. The vent for the rear cabin area on the passenger side blows air all the time no matter which mode is selected I tried manually calibrating the mode door by following this procedure from the Chilton's diy manual; see attached image. I don't have a scan tool and don't know if that's required to complete the recalibration or if I have another problem. Please help!

Images (Click to make bigger)

Thursday, September 16th, 2021 AT 2:30 PM

6 Replies

JACOBANDNICKOLAS

MECHANIC
110,176 POSTS

Hi,

Normally, a scan tool is used to prompt the control module. However, try this:

1. Turn the key off.

2. Disconnect the battery and remove the HVAC control module fuse.

3. Allow the vehicle to sit for approximately five minutes.

4. Reinstall the fuse and connect the battery.

5. Enter the vehicle and turn the key on. Don't try adjusting anything.

6. At this point, the control module should automatically recalibrate the system.

7. When you hear the actuators stop, turn the key off and then back on to see if that took care of the problem.

If it doesn't, then you will need a scan tool that can communicate with the HVAC control module. If you look at the attachments below, they provide the directions.

Let me know if this helps or if you have other questions.

Take care,

Joe

See pics below.

Images (Click to make bigger)

Was this

answer

helpful?

Yes

Friday, September 17th, 2021 AT 5:22 PM

6MIKE60

MEMBER
4 POSTS

Unfortunately this did not work. I'll check around and see if I can find a shop with a Scan tool that will do the calibration for a reasonable price. My local dealer gets $195.00/hour and the service writer wants 3 hour minimum to look at it. It's not worth $600.00 to me. Thank you for the answer.

Was this

answer

helpful?

Yes

Sunday, September 19th, 2021 AT 8:23 PM

JACOBANDNICKOLAS

MECHANIC
110,176 POSTS

Wow! $195.00 an hour? I would feel the same as you. If, however, you have it done and have a chance, I would really like to know is found and if it's taken care of.

$600.00 to diagnose. I used to buy good vehicles needing nothing for that amount. LOL Things are getting out of control anymore. I guess I'm showing my age.

Take good care of yourself,

Joe

Was this

answer

helpful?

Yes

Monday, September 20th, 2021 AT 5:19 PM

6MIKE60