2010 Sierra Heated seats will not work manually after starting remotel

[Enimo]

New to the forum and really need help...My son just purchased a 2010 Sierra, All-Terrain Z71 with all the options including remote start. I have searched every forum possible and have not found this particular issue. After starting the truck with remote we are unable to manually turn the heated seats on. I understand the if the temp is cold they will come on automatically but it is only 58 degrees here and we wanted to just try the out. He starts the truck with remote, puts key in ignition and as we are driving attempts to turn on the heated seats and they will not come on. Can someone please help me out?? I have spoken to the dealer and will have to leave for awhile just "check out". I do not trust them. Help please.

 

Thanks

[MikeNH]

Factory remote start or aftermarket?

[Enimo]

Factory...once last night they came on for a few seconds after remote starting but went right back off. This morning they do not come on at all but work perfectly when starting with key.

[MikeNH]

That really sounds like some kind of BCM error. Unless you know someone with a Tech II scanner I'm afraid you're going to have to visit the dealership.

[gmtech4]

Factory Installed Heated Seat System

Operation

 

 

The driver and passenger heated seats are controlled by separate heated seat

switches located in the door panels. Ground is supplied to the heated seat

switches through the switch low reference circuits from their respective door

lock/window switches. The door lock/window switches also control the heated seat

switch heat mode and temperature indicators. The memory seat module (MSM)

controls the heated seat operation for both front heated seats.

 

The following describes the sequence of operation and how the MSM responds to

each of the switch inputs.

• High Temperature—When the heated seat switch is pressed once, ground is

  applied through the switch contacts and the switch signal circuit to the door

  lock/window switch indicating the high heat request. In response to this signal,

  the door lock/window switch applies a low current voltage through the

  3 temperature indicator control circuits illuminating all 3 LEDs indicating the

  high temperature mode. The switch then sends a message via the GMLAN serial data

  line to the MSM indicating the heated seat request. The MSM then applies battery

  voltage through the heating element supply voltage circuit to the seat cushion

  and seat back heating elements. At the same time, it supplies a ground through

  the element low reference circuits to the seat heating elements.

• Medium Temperature—When the switch is pressed a second time, the MSM sets

  the temperature level to medium heat. The door lock/window switch removes the

  voltage from the high temperature indicator leaving 2 LEDs illuminated

  indicating the medium temperature mode.

• Low Temperature—When the switch is pressed a third time, the MSM sets the

  temperature level to low heat. The door lock/window switch removes the voltage

  from the medium temperature indicator leaving 1 LED illuminated indicating the

  low temperature mode.

• System OFF State—When the switch is pressed a fourth time, the MSM removes

  the battery voltage and grounds from the heating elements. The door lock/window

  switch removes the voltage from the low temperature indicator, indicating the

  system OFF state.

• Back Only Mode—When the heated seat is ON and the BACK ONLY mode button is

  pressed, ground is applied through the switch contacts and the heated seat back

  only mode signal circuit to the door lock/window switch. In response to this

  signal, the door lock/window switch sends a GMLAN message to the MSM indicating

  the back only mode request. The MSM then opens the ground path to the seat

  cushion heater element, leaving the seat back heater active. The door

  lock/window switch turns OFF the seat cushion/back mode indicator, then applies

  a low current voltage through the heated seat back only mode indicator control

  circuit illuminating the back only mode indicator.

and why dont you trust them ?

[gmtech4]

do you have RPO AN3 or KB6 ?

 

i found this also

 

 

Heated Seat Operation with Remote
Vehicle Start

The heated seats will turn ON with a remote start only with cooler outside
air temperatures and if the vehicle is equipped with an automatic climate
control system.

When the remote start button is pressed and the HVAC control module senses
cooler outside air temperatures, it sends a serial data message to the MSM
commanding it to activate the heated seats. The heated seats will stay ON for
approximately 10 minutes or until the ignition is turned to the ON/RUN position.
Once the ignition is turned to the ON/RUN position the heated seats will have to
be manually turned ON and OFF.

[gmtech4]

some schmatics show them having a control module for the heated seats which means the possiblities of DTCs

within the system,

 

let me know above RPO codes on glove box door,,so i can post schematics,,,,

[ponchonutty]

I seen this once before in a Silverado. Dealership had to reflash the BCM and that corrected the issue. They weren't sure why it had done that but suspected a previous bad reflash for the problem.

[Enimo]

Thanks to everyone who has replied to my issue...as I stated in one of my follow-up responses, it now does not appear to be related to the remote starting. It really just happens intermittently. They will work sometimes and sometimes they will not, all other seat functions work perfectly for both seats. Also, when one seat works they both work, when one doesn't work, neither do.

 

Thanks again,

Eddie