Battery module is missing do not use write back mode

Heated Seat System Operation
The driver and passenger heated seats have 2 heat zone operating modes with 3 heat level modes and will operate only while the engine is running. The heat zones are determined by which of the 2 heated seat buttons are pressed, while the heat level is determined by the number of times they are pressed. Pressing the seat cushion button 1 time will activate the seat back and cushion heater elements in the high mode. Each time the seat cushion button is pressed the seat back and cushion heat level is reduced from high to medium, low, and off. Pressing the heated seat back button 1 time will activate only the seat back heater element in the high mode. Each time the seat back button is pressed the seat back heat level is reduced from high to medium, low, and off. During heated seat operation the heat zone operating mode may be changed without affecting the current heat level mode.
The heated seat switches are momentary contact switches and are inputs to the driver and passenger door modules. Battery voltage is supplied to the switch assembly from the door module, and when a heated seat switch is pressed and released a brief switch signal voltage is supplied to the door module. Whenever the door module receives an active heated seat switch input, the next heated seat operating mode is determined by whatever the current mode may be. The seat heater elements are controlled by the driver seat module using inputs from the door modules through Class 2 serial data circuit messages. The driver seat module controls the voltage supply and the ground circuits to the seat heater elements. When a heated seat function is commanded active, the seat module will switch battery voltage to the heater element supply circuits, and ground is provided through low side drive control circuits. During heated seat operation both the seat back and cushion heater elements are supplied battery voltage. The seat module grounds the appropriate control circuits for back only or back and cushion heating modes, and opens or closes the active control circuits as necessary in order to maintain the desired seat temperature. The seat module relies on inputs from thermistors located in the driver and passenger seat backs to control heated seat temperatures. The thermistors are 2 wire sensors supplied with a 5-volt referenced signal circuit and a low reference circuit from the seat module. Resistance through the thermistors varies with temperature causing the heated seat sensor signal circuit voltage levels to decrease as the seat back temperatures rise. The seat modules allow heated seat operation only while the engine is running which is determined by a Class 2 serial data circuit message from the powertrain control module.

Heated Seat Components
The heated seat system consists of the following components:
• Driver and passenger heated seat switches
• Driver and passenger seat back heater elements
• Driver and passenger seat cushion heater elements
• Driver and passenger seat back temperature sensors
• Driver seat module
• Driver door module
• Passenger door module

Do you know what B - body DTC -diagnostic trouble code are ?
DTC B2425 Driver Seat Heater Circuit
DTC B2435 Driver Seat Back Heater Sensor Circuit
DTC B3941 Front Seat Heaters Circuit

Heated Seat Always On
Step
Action
Yes
No
Schematic Reference: Driver Seat Schematics and Passenger Seat Schematics
Connector End View Reference: Power Seat Connector End Views
1
Did you perform the Diagnostic System Check - Vehicle?
Go to Step 2
Go to Diagnostic System Check - Vehicle in Vehicle DTC Information
2
Operate the heated seat system.
Does the system operate normally?
Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems
Go to Step 3
3
Install a scan tool.
Display the Heated Seat Status parameter in the driver seat module Input/Output data list.
Start the engine.
Does the scan tool display the Heated Seat Status parameter as Off?
Go to Step 6
Go to Step 4
4
Display the Heated Seat Mode parameter in the door module Inputs data list.
Does the scan tool display the Heated Seat Mode parameter as OFF?
Go to Step 6
Go to Step 5
5
Turn OFF the ignition.
Disconnect the heated seat switch connector to the door module.
Start the engine.
Does the scan tool display the Heated Seat Mode parameter as OFF?
Go to Step 7
Go to Step 8
6
Replace the driver seat module. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming.
Is the repair complete?
Go to Step 9
--
7
Replace the heated seat switch. Refer to Front Seat Heater Switch Replacement .
Is the repair complete?
Go to Step 9
--
8
Replace the door module. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming.
Is the repair complete?
Go to Step 9
--
9
Operate the system in order to verify the repair.
Did you correct the condition?
System OK
Go to Step 3


your best bet , have a qualified repair shop diagnose the problem

Not a fuse issue , more then likely a burnt heating element in the seat , happens all the time .
Heated Seat Components
The heated seat system consists of the following components:
• Driver and passenger heated seat switches
• Driver and passenger seat back heater elements
• Driver and passenger seat cushion heater elements
• Driver and passenger seat back temperature sensors
• Driver seat module
• Driver door module
• Passenger door module

The control module have a Battery voltage supply , the module supply's voltage to the seat heating elements .
The heated seat switches are momentary contact switches and are inputs to the driver and passenger door modules. Battery voltage is supplied to the switch assembly from the door module, and when a heated seat switch is pressed and released a brief switch signal voltage is supplied to the door module. Whenever the door module receives an active heated seat switch input, the next heated seat operating mode is determined by whatever the current mode may be. The seat heater elements are controlled by the driver seat module using inputs from the door modules through Class 2 serial data circuit messages. The driver seat module controls the voltage supply and the ground circuits to the seat heater elements. When a heated seat function is commanded active, the seat module will switch battery voltage to the heater element supply circuits, and ground is provided through low side drive control circuits. During heated seat operation both the seat back and cushion heater elements are supplied battery voltage. The seat module grounds the appropriate control circuits for back only or back and cushion heating modes, and opens or closes the active control circuits as necessary in order to maintain the desired seat temperature. The seat module relies on inputs from thermistors located in the driver and passenger seat backs to control heated seat temperatures. The thermistors are 2 wire sensors supplied with a 5-volt referenced signal circuit and a low reference circuit from the seat module. Resistance through the thermistors varies with temperature causing the heated seat sensor signal circuit voltage levels to decrease as the seat back temperatures rise. The seat modules allow heated seat operation only while the engine is running which is determined by a Class 2 serial data circuit message from the powertrain control module.

Your best bet , take it to a qualified repair shop.

Need better info.
when shut off no start batt dead and ignition fuse in bjb replace fuse and still no start or crank no power to cluster cluster dead on commute back ????????? What about ignition fuse ? It was blown an you replaced it or you just replaced it ???? When you shut it off no restart ,the battery was dead ? Test battery , battery cable connections , charging system - is it charging ?
First off your probably unaware of how this vehicle works , This vehicle is powered up by the BCM turning on relays an sending commands over the serial data bus (network) ,do you know what that is ? The ignition switch is a low voltage input to the BCM .
Circuit Description (Key Start)
For ignition switch power modes refer to Body Control System Description and Operation . When the ignition switch is placed in the Start position a discrete signal is supplied to the body control module (BCM) notifying it that the ignition is in the Start position. The BCM then sends a message to the powertrain control module (PCM)/engine control module (ECM) notifying it that CRANK has been requested. At the same time the BCM is supplying 12 volts for the IGN 1 relay closing it and supplying battery positive voltage for the crank relay coil. The PCM/ECM verifies that the transmission is in Park or Neutral. If it is, the PCM/ECM grounds the control circuit of the crank relay. When this occurs battery positive voltage is supplied through the switch side of the crank relay to the S terminal of the starter solenoid.

Check the Ignition 1 relay -
Relay Controlled Power Mode
The body control module (BCM) uses the discrete ignition switch inputs ignition 1, ignition 3 and crank to distinguish the correct power mode. Once the BCM has determined the power mode selected by the vehicle operator it will energize the Ignition relay, Run relay and retained accessory power (RAP) relay, depending on which power mode is selected.
Ignition 1 Relay
The relay uses a Hot At All Times B+ power source derived from the underhood electrical center. The ignition 1 relay supplies a power signal to the following circuits when the Run or Crank power mode is selected:
• AC clutch relay
• ABS STG angle sensor
• Antilock brake system (ABS) yaw sensor
• Auxiliary power drop connector
• Crank relay
• Cruse control switch
• Electronic brake control module (EBCM)
• Engine control module (ECM)
• HVAC module
• Ignition control module (ICM)
• Instrument panel cluster (IPC)
• Sensing and diagnostic module (SDM)
• Transmission solenoid circuit

Looking at a wiring diagram for the passenger seat an checking wiring colors mite help you figure it out . But then again maybe not . Electronic's involved here , Right door module .
Heated Seat Components
The heated seats consist of the following components:
• Left heated seat switch
• Right heated seat switch
• Memory seat module
• Left door module
• Right door module
• Left seat cushion heating element
• Left seat back heating element
• Left seat cushion temperature sensor
• Right seat cushion heating element
• Right seat back heating element
• Right seat cushion temperature sensor
Modes of Operation
The heated seat module (MSM) controls heated seat operation for both the driver and passenger seats. There are 2 modes of operation available for heated seats; both the seat cushion and seat back heat, or seat back only heat. When a heated seat temperature signal request is received, the MSM will activate both the seat cushion and seat back heating elements. When the heated seat BACK ONLY mode button is pressed once the MSM will deactivate the seat cushion heating element and leave the seat back heating element ON.

Heated Seat Switch/LED Indicators and System Operation
The left and right 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 modules. The door modules also control the heated seat switch heat mode and temperature indicators. The memory seat module (MSM) controls the heated seat operation for both, the left and right 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 module indicating the high heat request. In response to this signal, the door module applies a low current voltage through the 3 temperature indicator control circuits illuminating all 3 LEDs indicating the high temperature mode. The module 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 module 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 module 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 module 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 module. In response to this signal, the door module 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 module 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.

Know how to test an what test is the key to finding the problem .Not guessing . The connector you found may or may not have anything to do with it . What color are the wires ? I have factory service repair manual . Does it have memory seats ?
The Memory Seat System consists of the following components:
• Memory seat module (MSM)
• Seat horizontal motor
• Seat front vertical motor
• Seat rear vertical motor
• Seat recline motor
• Lumbar horizontal motor
• Seat horizontal position sensor
• Seat front vertical position sensor
• Seat rear vertical position sensor
• Seat recline position sensor
• Lumbar horizontal positional sensor
• Seat adjuster switch
• Seat lumbar switch
• Memory seat switch
• PWR SEATS Circuit Breaker 30 A
• MEMORY RPA Fuse 7.5 A

28D6 HO-Protocol Failure coding missing means one of the modules is not communicating with the cars network that links all the modules. What symptoms do you have, cluster issues?.

Have you pulled the error codes?

1- Turn Ignition switch to OFF & Run/Stop switch is to Run.
2- Push odometer reset button in & hold.
3- Turn ignition switch to Ignition and release odometer reset button. Background lighting sould illuminate, speedometer needle should sweep its full range and indicator lamps (battery, security, low fuel, check engine and cruise) should illuminate. The word "diag" should then appear.
4 - Push the odometer reset button once and you will see the selection menu "PSSPt" with the first P flashing.
5 - Each letter represents an area of the diagnostics module. The module that is flashing is the one you are going to check. To move from one letter (module) to the next, you push the odometer reset button one time. (from P to S to SP to t and back to P, etc.)
P = ECM/ICM (Electronic Control Module [EFI] / Ignition Control Module [Carbureted])
S = TSM/TSSM (Turn Signal/ Turn Signal Security Module)
SP = speedometer
T = tachometer
6 - To get the DTC within an area of diagnostics, push and hold the odometer reset button in for 5 seconds and release. If there are any DTC's the code will be displayed or the word "none" will appear if there are no DTC's. Push the odometer reset button again to view additional codes if they exist.
7 - Record the codes.
8 - If DTC's are not to be cleared, Press and release the odometer reset button. Part number of module will be displayed.
NOTE: To determine if a code is current or historic, clear the displayed code by pushing in and holding the odometer reset button ( longer than 5 seconds) until 'clear' comes up. Release the odometer reset button. Turn OFF the ignition switch. Run your bike and shut it down then recheck the DTC's again by repeating steps 1 to 9. If the code is current it will reappear.
9 - Press and release the odometer reset button to continue to the next module.
10 - Turn Ignition switch to OFF.

What do the codes mean?

DTC FAULT CONDITION MODULE
"BUS Er" (TSM/HFSM) Serial Data Open/High
B0563 Battery Voltage High (TSM/TSSM)
B1004 Fuel Level Sending Unit Low (Instruments)
B1005 Fuel Level Sending Unit High/Open (Instruments)
B1006 Accessory Line Overvoltage (Instruments)
B1007 Ignition Line Overvoltage (Instruments)
B1008 Reset Switch Closed (Instruments)
B1121 Turn Signal Will Not Flash (HFSM)
B1122 Right Turn Signal Open (TSM)
B1123 Left Turn Signal Short-to-Ground (HFSM)
B1124 Right Turn Signal Short-to-Ground (HFSM)
B1125 Left Turn Signal Short-to-Voltage (HFSM)
B1126 Right Turn Signal Short-to-Voltage (HFSM)
B1134 Starter Output High ((TSM/TSSM)
B1135 Accelerometer Fault ((TSM/TSSM)
B1136 Accelerometer Tip-Over Self Test (HFSM)
B1141 Ignition Switch Open/Low (HFSM) ONLY
B1141 Turn signals Will Not Flash (TSM) ONLY
B1142 Internal Fault (HFSM)
B1143 Security Antenna Short-to-Ground (HFSM)
B1144 Security Antenna Short-to-Battery (HFSM)
B1145 Security Antenna Open (HFSM)
B1151 Sidecar BAS Low ((TSM/TSSM)
B1152 Sidecar BAS High ((TSM/TSSM)
B1153 Sidecar BAS Out of Range ((TSM/TSSM)
B1154 Clutch Switch Short-to-Ground (TSM/HFSM)
B1155 Neutral Switch Short-to-Ground (TSMHFSM)
B2006 Radio Switches Shorted/Stuck (Audio)
B2007 Handlebar (Audio) Switch Shorted High(Audio)
Handlebar Mode Switch Shorted High(Audio)
Handlebar PTT/Squelch Switch Shorted High(Audio)
B2008 Handlebar (Audio) Switch Shorted Low(Audio)
Handlebar Mode Switch Shorted Low(Audio)
Handlebar PTT/Squelch Switch Shorted Low(Audio)
B2009 Handlebar (Audio) Switch Stuck or Open(Audio)
Handlebar Mode Switch Stuck or Open(Audio)
Handlebar PTT/Squelch Switch Stuck or Open(Audio)
B2010 Passenger (Audio)/PTT Switch Shorted High(Audio)
Passenger Mode Switch Shorted High(Audio)
B2011 Passenger (Audio)/PTT Switch Shorted Low(Audio)
Passenger Mode Switch Shorted Low(Audio)
B2012 Passenger (Audio)/PTT Switch Shorted Stuck or Open(Audio)
Passenger Mode Switch Shorted Stuck or Open(Audio)
B2013 Sidecar Switches Shorted High(Audio)
B2014 Sidecar Switches Shorted Low(Audio)
B2015 Sidecar Switches Shorted Stuck or Open(Audio)
B2016 Front Speakers Shorted(Audio)
B2017 Front Speakers Open(Audio)
B2018 Front Speakers Shorted to Ground(Audio)
B2019 Front Speakers Shorted to Battery(Audio)
B2020 Rear Speakers Shorted(Audio)
B2021 Rear Speakers Open(Audio)
B2022 Rear Speakers Shorted to Ground(Audio)
B2023 Rear Speakers Shorted to Battery(Audio)
B2024 Sidecar Speakers Shorted(Audio)
B2025 Sidecar Speakers Open(Audio)
B2026 Sidecar Speakers Shorted to Ground(Audio)
B2027 Sidecar Speakers Shorted to Battery(Audio)
P0107 Map Sensor Open/Low (EFI)
P0108 Map Sensor High (EFI)
P0112 IAT Sensor Voltage Low (EFI)
P0113 IAT Sensor Voltage Open/High (EFI)
P0117 ET Sensor Voltage Low (EFI)
P0118 ET Sensor Voltage Open/High (EFI)
P0122 TP Sensor Open/Low (EFI)
P0123 TP Sensor High (EFI)
P0131 Front O2 Sensor Low (EFI)
P0132 Front O2 Sensor High (EFI)
P0134 Front O2 Sensor Open/Not Responding (EFI)
P0151 Rear O2 Sensor Low (EFI)
P0152 Rear O2 Sensor High (EFI)
P0154 Rear O2 Sensor Open/Not Responding (EFI)
P0261 Front Injector Open/Low (EFI)
P0262 Front Injector High (EFI)
P0263 Rear Injector Open/Low (EFI)
P0264 Rear Injector High (EFI)
P0373 CKP Sensor Intermittent (EFI)
P0374 CKP Sensor Synch Error (EFI)
P0501 VSS Low (EFI)
P0502 VSS High/Open (EFI)
P0505 Loss of Idle Sped Control (EFI)
P0562 Battery Voltage Low (EFI)
P0563 Battery Voltage High (EFI)
P0603 ECM EEPROM Error (EFI)
P0605 ECM Flash Error (EFI)
P0661 Active Intake Solenoid Open (EFI)
P0662 Active Intake High/Shorted (EFI)
P1001 System Relay Coil Open/Low (EFI)
P1002 System relay Coil High/Shorted (EFI)
P1003 System relay Contacts Open (EFI)
P1004 System Relay Contacts Closed (EFI)
P1009 Incorrect Password (EFI)
P1010 Missing Password (EFI)
P1351 Front Ignition Open/Low (EFI)
P1352 Front Ignition Coil High/Shorted (EFI)
P1353 Front Cylinder No Combustion (EFI)
P1354 Rear Ignition Coil Open/Low (EFI)
P1355 Rear Ignition Coil High/Shorted (EFI)
P1356 Rear Cylinder No Combustion (EFI)
P1357 Intermittent Secondary Front (EFI)
P1358 Intermittent Secondary Rear (EFI)
P1475 Exhaust Actuator Position Error (EFI)
P1477 Exhaust Actuator Open/Low (EFI)
P1478 Exhaust Actuator Shorted (EFI)
U1016 Loss of ICM/ECM Serial Data (Instruments)
U1016 Loss of Serial Data(Audio)
U1016 Loss of ECM Serial Data (TSM/HFSM))
U1064 Loss of (TSM/TSSM) Serial Data (EFI)
U1064 Loss of (TSM/TSSM/HFSM) Serial Data (Instruments)
U1097 Loss of Speedometer Serial data (EFI)
U1255 Missing Message at Speedometer (EFI)
U1255 Serial Data Error/Missing Message (EFI)
U1255 Serial Data Error/Missing Message (Instruments)
U1255 Serial Data Error/Missing Message (TSM/TSSM/HSFM)
U1300 Serial Data Low (EFI)
U1300 Serial Data Low (Instruments)
U1300, U1301 Stalls, then Starts(Audio)
U1300 Serial Data Low (TSM/HFSM)
U1301 Serial Data Open/High (EFI)
U1301 Serial Data Open/High (Instruments)
U1301 Serial Data Open/High (TSM/TSSM)
U1302 Infotainment BUS Shorted Low/High(Audio)
U1306 Infotainment BUS Lost Communications with Hands free Phone Module(Audio)
U1307 Infotainment BUS Lost Communications with CB Module(Audio)
U1313 Infotainment BUS Lost Communications with XM Module(Audio)
U1314 Infotainment BUS Lost Communications with Navigation Module(Audio)
U1317 Infotainment BUS Lost Communications with High Output Amplifier(Audio)

There are disconnects between the power modules and the circuitry within the interstice devices contained within the modular adapter. Failure to negate to consumption and communicating protocol as per the advanced module attached to the formulations concept board, only further damaging the battery module as per the mode block notification process.

Without trouble shooting ,would only be guessing . Could be any number of thing's . You have no idea the complexity of the electronic's on this vehicle . All the different control modules , serial data communication network . You probably don't even know what's happening just turning the key to start the start position .
For ignition switch power modes refer to Body Control System Description and Operation. Once the ignition is placed in the Run/Crank position, the control circuit of the Run/Crank relay is grounded by the body control module (BCM). With the Run/Crank relay switch closed, battery positive voltage flows through it and on to the park/neutral position (PNP) switch. With the PNP switch in either the Park or Neutral position, battery positive voltage will flow to the starter relay coil supply voltage input terminal of the powertrain control module and the coil side of the starter relay. Placing the ignition in the START position sends a message to the engine control module (ECM)/powertrain control module (PCM) requesting engine start. If the ECM/PCM has determined that the transmission is in Park or Neutral and theft is not active, it will ground the control circuit of the starter relay. Battery positive voltage will then flow through the switch side of the starter relay to the S terminal of the starter solenoid, cranking the engine. For remote vehicle start (RVS) information, refer to Keyless Entry System Description and Operation.

Power Mode Master
This vehicles body control module (BCM) functions as the power mode master (PMM). Refer to Power Mode Description and Operation for a complete description of power mode functions.

Power to many of this vehicle's circuits are controlled by the module that is designated the power mode master (PMM). This vehicle's PMM is the body control module (BCM). The PMM controls which power mode (Run, Accessory, Crank, Retained Accessory Power, or Off) is active.
Serial Data Power Mode Master
On vehicles that have several control modules connected by serial data circuits, one module is the power mode master (PMM). On this vehicle, the PMM is the body control module (BCM). The PMM receives 3 discrete ignition switch signals to differentiate which power mode will be sent over the Serial Data circuits. The 3-wire Ignition Switch table below illustrates the state of these inputs in correspondence to the ignition switch position:

Relay Controlled Power Mode
The body control module (BCM) uses the discrete ignition switch inputs Off/Run/Crank, Accessory, and ignition 1, to distinguish the correct power mode. The ignition 1 circuit is also routed to the Run/Crank relay for relay controlled power feeds during the appropriate power mode. The BCM, after determining the desired power mode, will activate the appropriate relays for that power mode.
The first step in the diagnostic procedure chart would be to hook up the Tech2 - factory scan tool an check all the modules on the vehicle for DTC'S - diagnostic trouble code's .
Your best bet have it towed to a qualified repair shop .

when turning the key to start and all the lights go off indicates a battery problem
could be dirty terminals and battery posts ( have to be shiny clean) and tight, bad ground wire to engine or bad cells in battery
it needs 12 volts to run the lights but when the starter is engaged the volts drop to below 6 volts , the lights go out

mcdevito75 here, Return to where the battery was changed, for adjustments.