caddy dealer didnt fix it, gotta try more digging
---------- Post added at 08:50 PM ---------- Previous post was at 07:25 PM ----------
here is what I am trying next:
Heated Seat Inoperative or Shuts off in 30 Seconds - B1825 B2435 B2440 B3606 - keywords driver left passenger right #PIT3287C - (Dec 7, 2005)
Heated Seat Inoperative or Shut Off In 30 Seconds B1825 B2435 B2440 B3606 2003-2006 Cadillac Escalade, Escalade ESV, Escalade EXT
2003-2006 Chevrolet Avalanche, Silverado, Suburban, Tahoe
2003-2006 GMC Sierra, Sierra Denali, Yukon, Yukon Denali, Yukon XL, Yukon Denali XL
2003-2006 Hummer H2
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
<A href="http://service.gm.com/servlets/BlobShtml?ShtmlFile=1740261&psdid=297&evc=sm#ss1-1740261">Condition/Concern:
Driver and passenger heated seats inoperative or shut off in 30 seconds. There will be DTCs B2435, B2440, B3606 and/or B1825 set in the Drivers Seat Module. The adjustable pedal position sensor, seat recliner position sensor and both heat seat thermistors share the same 5 volt reference internal to the Drivers Seat Module. A fault in any of these components/circuits can make the heated seats inoperative or shut off in 30 seconds, as well as, the seat recliner and/or adjustment pedals may move in short increments when operated. A fault in either heated seats, adjustable pedal or seat recliner will affect BOTH heated seats.
Note: If vehicle is not equipped with adjustable pedals DTC B3606 will not set.
<A href="http://service.gm.com/servlets/BlobShtml?ShtmlFile=1740261&psdid=297&evc=sm#ss2-1740261">Recommendation/Instructions:
To help isolate the area of concern use the Tech 2 and go to "Sensor Data" in the Drivers Seat Module. Monitor the following parameters for being out of range:
Recline Position- Normal range .39V-4.58V
Pedal Position (if equipped) - Normal range .39V-4.58V
Psgr. Seat Heat Sensor- Normal range 1V-4V
Drvr. Seat Heat Sensor- Normal range 1V-4V
If a parameter is found to be out of range inspect circuits for any opens, shorts to ground, or voltage. If none found replace the suspect component.
Please be aware of the following common areas of concern:
<LI type=1>The adjustable pedal position sensor internally shorted pulling the 5 volt reference low. Disconnect the adjustable pedal position sensor and see if the heated seats start working correctly, if so replace. Important: The APP (Accelerator Pedal Position) sensor is NOT the adjustable pedal position sensor. Make sure the correct sensor, adjustable pedal position sensor, is disconnected.
<LI type=1>The seat recliner position sensor internally shorted pulling the 5 volt reference low. Disconnect the recliner position sensor and see if heated seats start working correctly, if so replace. <LI type=1>An open in either heated seat thermistor circuits (signal or low reference). The most common is the passenger thermistor where it passes through seat connector C305 pin "L" or "K" or C399 pins "R" or "G".
A chaff to ground on either heated seat thermistor signal circuits. The most common is circuit 5475 black/red or dark blue shorted to ground in the passenger seat near the buckle. Important: The heated seat thermistors act differently to "OPENS and SHORTS" than the adjustable pedal position sensor and seat recliner position sensor. The adjustable pedals and seat recliner sensors can be disconnected for testing of the heated seats. Where as the heated seat thermistor circuit must be working correctly before EITHER heated seat will operate. Disconnecting one thermistor, which may have a concern will not allow the opposite heated seat to work correctly, BOTH side must be operational before EITHER heated seat will operate.
<A href="http://service.gm.com/servlets/BlobShtml?ShtmlFile=1740261&psdid=297&evc=sm#ss3-1740261">Clearing DTCs
If DTCs will not clear when using the Tech 2 after a repair has been made, try operating the device in which the repair was made. Example, if a repair was made to the passenger heated seat thermistor circuit, the DTCs may not clear unless the passenger heated seat is operated.
