Diagnostic Routine AD
Diagnostic Routine AD
Diagnostic Overview
B272A
Refer to Wiring Diagram Set 119, Climate Controlled Seats for schematic and connector information. Diagrams By Number
Normal Operation and Fault Conditions
DTC Fault Trigger Conditions
Pinpoint Test
NOTICE: When taking measurements at DCSM (Dual Climate Controlled Seat Module) harness connectors, do not insert the electrical probes into the female connector pins. Inserting the probes into connector pins can cause intermittent or open electrical connections after reassembly resulting in DTCs (Diagnostic Trouble Codes) and system failure. Touching the tip of these connector pins is recommended instead.
1. CHECK THE DCSM (Dual Climate Controlled Seat Module) FOR DTC (Diagnostic Trouble Code)
1. Using a scan tool, perform DCSM (Dual Climate Controlled Seat Module) self-test.
Was DTC (Diagnostic Trouble Code) B272A retrieved during the self-test?
2. CHECK THE TED (Thermo-Electric Device) THERMISTOR CIRCUITS FOR A SHORT TO GROUND
1. WARNING: Turn the ignition OFF and wait one minute to deplete the backup power supply. Failure to follow this instruction may result in serious personal injury or death in the event of an accidental deployment.
Ignition OFF.
2. Disconnect: Passenger Seat Side Air Bag C339.
3. Disconnect: DCSM (Dual Climate Controlled Seat Module) C3265B.
4. Disconnect: Passenger Cushion TED (Thermo-Electric Device) C3040.
5. Measure:
Are the resistances greater than 10,000 ohms?
3. CHECK THE TED (Thermo-Electric Device) THERMISTOR
1. Measure:
Is the resistance within the limits indicated?
4. CONFIRM THE FAULT
1. Verify with the customer that the concern is the seat shuts off in heat mode.
2. NOTE: A crushed seat cushion foam pad or climate controlled seat manifold may be the cause of the fault. It may be necessary to sit on the seat or place something of reasonable size and weight on the seat to recreate the fault.
Attempt to recreate the fault. Start the vehicle and set the passenger seat to HIGH heat for at least 15 minutes.
Is the customer concern with the seat shutting off in heat mode and was the fault recreated?
5. CHECK OPERATION OF THE SEAT
1. Ignition ON.
2. With the engine running, set both front seats to HIGH cool.
3. Compare the air flow from the passenger seat cushion to the air flow from the driver seat cushion.
Is the air flow exhausting from the passenger seat cushion comparable to the air flow exhausting from the driver seat cushion?
6. CHECK THE CUSHION BLOWER FOR AN OBSTRUCTION OR RESTRICTED FILTER
1. Ignition OFF.
2. Inspect the blower of the cushion TED (Thermo-Electric Device) assembly for an obstruction or for a restricted filter.
Is the blower obstructed or the filter restricted?
7. CHECK THE CUSHION FAN OPERATION
1. Ignition ON.
2. With the engine running, set both front seats to HIGH cool.
3. Inspect the cushion blower for operation.
Does the cushion blower operate?
8. CHECK THE BLOWER SPEED CONTROL CIRCUIT FOR AN OPEN
1. WARNING: Turn the ignition OFF and wait one minute to deplete the backup power supply. Failure to follow this instruction may result in serious personal injury or death in the event of an accidental deployment.
Ignition OFF.
2. Disconnect: Passenger Seat Side Air Bag C339.
3. Disconnect: DCSM (Dual Climate Controlled Seat Module) C3265C.
4. Disconnect: Passenger Cushion TED (Thermo-Electric Device) C3040.
5. Measure:
Is the resistance less than 3 ohms?
9. CHECK THE BLOWER CIRCUIT FOR A SHORT TO VOLTAGE
1. Ignition ON.
2. Measure:
Is any voltage present?
10. CHECK BLOWER CIRCUIT FOR A SHORT TO GROUND
1. Ignition OFF.
2. Measure:
Is the resistance greater than 10,000 ohms?
11. CHECK BLOWER CIRCUITS FOR AN OPEN
1. Measure:
Are the resistances less than 3 ohms?
12. CHECK THE BLOWER RESISTANCE
1. NOTICE: Connect the ohmmeter with the positive lead to pin 2 and the negative lead to pin 4 when measuring. Ohmmeter leads incorrectly connected can result in false readings and lead to incorrect identification of components that are not damaged.
Measure:
Is the resistance between 4,000 ohms and 10,000 ohms?
13. CHECK THE BLOWER SPEED CONTROL RESISTANCE
1. NOTICE: Connect the ohmmeter with the positive lead to pin 7 and the negative lead to pin 4 when measuring. Ohmmeter leads incorrectly connected can result in false readings and lead to incorrect identification of components that are not damaged.
Measure:
Is the resistance between 240,000 ohms and 420,000 ohms?
14. CHECK THE TED (Thermo-Electric Device) INSTALLATION AND FOR CRUSHED SEAT CUSHION
1. Ignition OFF.
2. Remove the seat. REFER to Seat Seat.
3. Remove the seat cushion cover. REFER to Seat Cushion Cover Seat Cushion Cover.
4. Inspect the seat cushion.
- Is the TED (Thermo-Electric Device) correctly installed?
- Is the seat cushion foam pad crushed or restricted?
- Is the climate controlled seat manifold crushed or restricted?
Is the TED (Thermo-Electric Device) correctly installed and are there no signs of damage to the foam pad and manifold?
15. CHECK FOR CORRECT DCSM (Dual Climate Controlled Seat Module) OPERATION
1. Ignition OFF.
2. Disconnect and inspect all DCSM (Dual Climate Controlled Seat Module) connectors.
3. Repair:
- corrosion (install new connector or terminals - clean module pins)
- damaged or bent pins - install new terminals/pins as necessary
- pushed-out pins - install new pins as necessary
4. Reconnect the DCSM (Dual Climate Controlled Seat Module) connectors. Make sure they seat and latch correctly.
5. Connect: Passenger Cushion TED (Thermo-Electric Device) C3040.
6. Operate the system and determine if the concern is still present.
Is the concern still present?
16. CHECK FOR SRS (Supplemental Restraint System) DTCs (Diagnostic Trouble Codes)
1. WARNING: Turn the ignition OFF and wait one minute to deplete the backup power supply. Failure to follow this instruction may result in serious personal injury or death in the event of an accidental deployment.
Ignition OFF.
2. Connect: Passenger Seat Side Air Bag C339.
3. Connect: DCSM (Dual Climate Controlled Seat Module) C3265B and C3265C (if previously disconnected).
4. Connect: Passenger Cushion TED (Thermo-Electric Device) C3040 (if previously disconnected).
5. Ignition ON.
6. Using a scan tool, clear the RCM (Restraints Control Module) DTCs (Diagnostic Trouble Codes).
7. Cycle the ignition OFF then ON.
8. Using a scan tool, perform RCM (Restraints Control Module) self-test.
Are any RCM (Restraints Control Module) DTCs (Diagnostic Trouble Codes) retrieved during self-test?
