Pinpoint Test As : DTC B272B
- AS1 CHECK THE Front Seat Climate Control Module (SCME) FOR ON-DEMAND DTCs
- Start the vehicle and set the passenger seat to HIGH heat.
- Enter the following diagnostic mode on the scan tool: Self Test - Front Seat Climate Control Module (SCME).
Was DTC B272B retrieved on-demand during the self-test?
Yes GO to AS2. No GO to AS5. - AS2 CHECK THE PASSENGER SEAT BACKREST TED THERMISTOR CIRCUITS FOR A SHORT TO GROUND
- Ignition OFF.
- Depower the SRS. Refer to SRS Depowering and Repowering in the General Procedures portion of Supplemental Restraint System .
- Disconnect: Passenger Seat Side Airbag C3052.
- Disconnect: Front Seat Climate Control Module (SCME) C3265B.
- Disconnect: Passenger Seat Backrest TED C3039.
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WARNING: Make sure no one is in the vehicle and there is nothing blocking or placed in front of any airbag when the battery is connected. Failure to follow these instructions may result in serious personal injury in the event of an accidental deployment.
Connect the battery ground cable. Refer to Battery, Mounting and Cables .
- Measure the resistance between:
- Front Seat Climate Control Module (SCME) C3265B-4 , circuit VHS36 (YE/BU), harness side and ground.
- Front Seat Climate Control Module (SCME) C3265B-5 , circuit RHS20 (GN/BU), harness side and ground.
Are the resistances greater than 10, 000 ohms?
Yes GO to AS3. No REPAIR the circuit(s). CLEAR the DTCs. REPEAT the self-test. DISCONNECT the battery ground cable. CONNECT passenger seat side airbag C3052. REPOWER the SRS. REFER to Supplemental Restraint System . - AS3 CHECK THE PASSENGER SEAT BACKREST TED THERMISTOR AND WIRING
- Connect: Passenger Seat Backrest TED C3039.
- Measure the resistance between Front Seat Climate Control Module (SCME) C3265B-4
, circuit VHS36 (YE/BU), harness side and Front Seat Climate Control Module (SCME) C3265B-5
, circuit RHS20 (GN/BU), harness side. Note the ambient temperature and refer to the following table.
Temperature Resistance 0-10 °C (32-50 °F) 2, 782-1, 663 ohms 10-20 °C (50-68 °F) 1, 837-1, 140 ohms 20-30 °C (68-86 °F) 1, 260-806 ohms 30-40 °C (86-104 °F) 893-570 ohms 40-50 °C (104-122 °F) 630-428 ohms
Is the resistance within the limits indicated?
Yes GO to AS18. No GO to AS4. - AS4 CHECK THE PASSENGER SEAT BACKREST TED THERMISTOR
- Disconnect: Passenger Seat Backrest TED C3039.
- Measure the resistance between passenger seat backrest TED C3039 pin 5 and pin 8, component side. Note the ambient temperature and refer to the following table.
Temperature Resistance 0-10 °C (32-50 °F) 2, 782-1, 663 ohms 10-20 °C (50-68 °F) 1, 837-1, 140 ohms 20-30 °C (68-86 °F) 1, 260-806 ohms 30-40 °C (86-104 °F) 893-570 ohms 40-50 °C (104-122 °F) 630-428 ohms
Is the resistance within the limits indicated?
Yes REPAIR circuit VHS36 (YE/BU)/VHS35 (VT/OG) or RHS20 (GN/BU)/RHS15 (GY/BN) for an open or high resistance. CLEAR the DTCs. REPEAT the self-test. DISCONNECT the battery ground cable. CONNECT passenger seat side airbag C3052. REPOWER the SRS. REFER to Supplemental Restraint System . No INSTALL a new passenger seat backrest TED. REFER to Seat Backrest Thermo-Electric Device . CLEAR the DTCs. REPEAT the self-test. DISCONNECT the battery ground cable. CONNECT passenger seat side airbag C3052. REPOWER the SRS. REFER to Supplemental Restraint System . - AS5 CONFIRM THE FAULT WHILE MONITORING THE Front Seat Climate Control Module (SCME) SEAT BACK THERMAL ELECTRIC DEVICE TEMPERATURE (PBKTEMP) AND SEAT CUSHION THERMAL ELECTRIC DEVICE TEMPERATURE (PCSHTEMP) PIDs
- Set the passenger seat to OFF.
- Enter the following diagnostic mode on the scan tool: Clear DTCs - Front Seat Climate Control Module (SCME).
- Enter the following diagnostic mode on the scan tool: DataLogger - Front Seat Climate Control Module (SCME).
- Monitor the Front Seat Climate Control Module (SCME) PIDs PBKTEMP and PCSHTEMP.
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NOTE: A crushed seat backrest foam pad or a crushed climate controlled seat manifold may be the cause of the fault making it necessary to occupy the seat to recreate and identify the fault.
Attempt to recreate the fault. Start the vehicle and set the passenger seat to HIGH heat for at least 15 minutes while occupying the seat.
Do the PIDs increase incrementally (gradually) and stay within 15 °C (27 °F) of each other?
Yes Fault not present at this time. Fault may have been set due to a past failure, incorrect use of the climate controlled seat system by repeated switching between heat and cool modes or due to excessive passenger compartment temperature. CLEAR the DTCs. REPEAT the self-test. No If the PBKTEMP PID increases incrementally and is greater than 15 °C (27 °F) of the PCSHTEMP PID, GO to AS6.If the PBKTEMP PID increases quickly (temperature "jumps" and does not increase incrementally) and is greater than 15 °C (27 °F) of the PCSHTEMP PID, GO to AS16. - AS6 COMPARE OPERATION OF THE DRIVER AND PASSENGER SEATS
- With the engine running, set both front seats to HIGH cool.
- Note the airflow exhausting from the passenger seat backrest TED and compare it to the airflow exhausting from the driver seat backrest TED.
- Carry out a wiggle test of the wire harnesses between the Front Seat Climate Control Module (SCME) and the passenger seat backrest TED while monitoring blower operation of the TED. The blower should operate consistently and not change speeds
Is the airflow exhausting from the passenger seat backrest TED comparable to the airflow exhausting from the driver seat backrest TED with no change in operation when carrying out the wiggle test?
Yes GO to AS7. No If the airflow exhausting from the passenger seat backrest TED is not comparable to the airflow exhausting from the driver seat backrest TED, GO to AS8.If the passenger seat backrest TED blower operation changed while carrying out the wiggle test, IDENTIFY and REPAIR the wiring fault. CLEAR the DTCs. REPEAT the self-test. - AS7 COMPARE OPERATION OF THE DRIVER AND PASSENGER SEATS WHILE OCCUPIED
- Note the airflow exhausting from the passenger seat backrest TED with the passenger seat occupied and compare it to the airflow exhausting from the driver seat backrest TED with the driver seat occupied.
Is the airflow exhausting from the passenger seat backrest TED comparable to the airflow exhausting from the driver seat backrest TED ?
Yes GO to AS16. No INSTALL a new passenger seat backrest foam pad and/or climate controlled seat manifold. CLEAR the DTCs. REPEAT the self-test. - AS8 CHECK THE PASSENGER SEAT BACKREST BLOWER FOR AN OBSTRUCTION OR RESTRICTED FILTER
- Ignition OFF.
- Inspect the blower of the passenger seat backrest TED assembly for an obstruction or for a restricted filter.
Is the blower obstructed or the filter restricted?
Yes REMOVE the obstruction or INSTALL a new filter. CLEAR the DTCs. REPEAT the self-test. No GO to AS9. - AS9 CHECK THE PASSENGER SEAT BACKREST BLOWER SPEED CONTROL CIRCUIT FOR AN OPEN
- Depower the SRS. Refer to SRS Depowering and Repowering in the General Procedures portion of Supplemental Restraint System .
- Disconnect: Passenger Seat Side Airbag C3052.
- Disconnect: Front Seat Climate Control Module (SCME) C3265C.
- Disconnect: Passenger Seat Backrest TED C3039.
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WARNING: Make sure no one is in the vehicle and there is nothing blocking or placed in front of any airbag when the battery is connected. Failure to follow these instructions may result in serious personal injury in the event of an accidental deployment.
Connect the battery ground cable. Refer to Battery, Mounting and Cables .
- Measure the resistance between Front Seat Climate Control Module (SCME) C3265C-4 , circuit CHS09 (GY), harness side and passenger seat backrest TED C3039-7 , circuit CHS04 (YE/GY), harness side.
Is the resistance less than 5 ohms?
Yes GO to AS10. No REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test. DISCONNECT the battery ground cable. CONNECT passenger seat side airbag C3052. REPOWER the SRS. REFER to Supplemental Restraint System . - AS10 CHECK THE PASSENGER SEAT BACKREST BLOWER CIRCUIT FOR A SHORT TO VOLTAGE
- Ignition ON.
- Measure the voltage between Front Seat Climate Control Module (SCME) C3265C-7 , circuit CHS08 (BN/YE), harness side and ground.
Is any voltage present?
Yes REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test. DISCONNECT the battery ground cable. CONNECT passenger seat side airbag C3052. REPOWER the SRS. REFER to Supplemental Restraint System . No GO to AS11. - AS11 CHECK THE PASSENGER SEAT BACKREST BLOWER CIRCUIT FOR A SHORT TO GROUND
- Ignition OFF.
- Measure the resistance between Front Seat Climate Control Module (SCME) C3265C-8 , circuit CHS14 (GN), harness side and ground.
Is the resistance greater than 10, 000 ohms?
Yes GO to AS12. No REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test. DISCONNECT the battery ground cable. CONNECT passenger seat side airbag C3052. REPOWER the SRS. REFER to Supplemental Restraint System . - AS12 CHECK THE PASSENGER SEAT BACKREST BLOWER CIRCUITS FOR AN OPEN
- Measure the resistance between:
Are the resistances less than 5 ohms?
Yes GO to AS13. No REPAIR the circuit(s). CLEAR the DTCs. REPEAT the self-test. DISCONNECT the battery ground cable. CONNECT passenger seat side airbag C3052. REPOWER the SRS. REFER to Supplemental Restraint System . - AS13 CHECK THE PASSENGER SEAT BACKREST BLOWER RESISTANCE
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NOTE: The ohmmeter must be connected with the positive lead to pin 2 and the negative lead to pin 4 when measuring. Ohmmeter leads incorrectly connected results in false readings and leads to incorrect identification of components that are not damaged.
Measure the resistance between passenger seat backrest TED C3039 pin 2 and pin 4, component side.
Is the resistance between 4, 000 ohms and 10, 000 ohms?
Yes GO to AS14. No INSTALL a new passenger seat backrest TED. REFER to Seat Backrest Thermo-Electric Device . CLEAR the DTCs. REPEAT the self-test. DISCONNECT the battery ground cable. CONNECT passenger seat side airbag C3052. REPOWER the SRS. REFER to Supplemental Restraint System . -
- AS14 CHECK THE PASSENGER SEAT BACKREST BLOWER SPEED CONTROL RESISTANCE
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NOTE: The ohmmeter must be connected with the positive lead to pin 7 and the negative lead to pin 4 when measuring. Ohmmeter leads incorrectly connected results in false readings and leads to incorrect identification of components that are not damaged.
Measure the resistance between passenger seat backrest TED C3039 pin 7 and pin 4, component side.
Is the resistance between 240K ohms and 400K ohms?
Yes GO to AS15. No INSTALL a new passenger seat backrest TED. REFER to Seat Backrest Thermo-Electric Device . CLEAR the DTCs. REPEAT the self-test. DISCONNECT the battery ground cable. CONNECT passenger seat side airbag C3052. REPOWER the SRS. REFER to Supplemental Restraint System . -
- AS15 CHECK THE PASSENGER SEAT BACKREST TED INSTALLATION AND FOR CRUSHED SEAT BACKREST
- Ignition OFF.
- Remove the passenger seat backrest cover. Refer to Seat Backrest Cover - Front .
- Inspect the passenger seat backrest for the following:
- Is the passenger seat backrest TED correctly installed?
- Is the passenger seat backrest foam pad crushed or restricted?
- Is the passenger seat backrest climate controlled seat manifold crushed or restricted?
Is the passenger seat backrest TED correctly installed and are there no signs of damage to the foam pad and manifold?
Yes INSTALL the passenger seat backrest cover and seat and GO to AS18. No CORRECTLY install the passenger seat backrest TED or INSTALL a new passenger seat backrest foam pad and/or climate controlled seat manifold. CONNECT the battery ground cable. REFER to Battery, Mounting and Cables . CLEAR the DTCs. REPEAT the self-test. DISCONNECT the battery ground cable. CONNECT passenger seat side airbag C3052. REPOWER the SRS. REFER to Supplemental Restraint System . - AS16 CHECK THE PASSENGER SEAT BACKREST TED THERMISTOR AND WIRING
- Ignition OFF.
- Depower the SRS. Refer to SRS Depowering and Repowering in the General Procedures portion of Supplemental Restraint System .
- Disconnect: Passenger Seat Side Airbag C3052.
- Disconnect: Front Seat Climate Control Module (SCME) C3265B.
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WARNING: Make sure no one is in the vehicle and there is nothing blocking or placed in front of any airbag when the battery is connected. Failure to follow these instructions may result in serious personal injury in the event of an accidental deployment.
Connect the battery ground cable. Refer to Battery, Mounting and Cables .
- Measure the resistance between Front Seat Climate Control Module (SCME) C3265B-4
, circuit VHS36 (YE/BU), harness side and C3265B-5
circuit RHS20 (GN/BU), harness side. Note the ambient temperature and refer to the following table.
Temperature Resistance 0-10 °C (32-50 °F) 2, 782-1, 663 ohms 10-20 °C (50-68 °F) 1, 837-1, 140 ohms 20-30 °C (68-86 °F) 1, 260-806 ohms 30-40 °C (86-104 °F) 893-570 ohms 40-50 °C (104-122 °F) 630-428 ohms
Is the resistance within the limits indicated?
Yes GO to AS18. No GO to AS17. - AS17 CHECK THE PASSENGER SEAT BACKREST TED THERMISTOR
- Measure the resistance between passenger seat backrest TED C3039 pin 5 and pin 8, component side. Note the ambient temperature and refer to the following table.
Temperature Resistance 0-10 °C (32-50 °F) 2, 782-1, 663 ohms 10-20 °C (50-68 °F) 1, 837-1, 140 ohms 20-30 °C (68-86 °F) 1, 260-806 ohms 30-40 °C (86-104 °F) 893-570 ohms 40-50 °C (104-122 °F) 630-428 ohms
Is the resistance within the limits indicated?
Yes REPAIR circuit VHS35 (VT/OG)/VHS36 (YE/BU) or RHS15 (GY/BN)/RHS20 (GN/BU) for an open or high resistance. CLEAR the DTCs. REPEAT the self-test. DISCONNECT the battery ground cable. CONNECT passenger seat side airbag C3052. REPOWER the SRS. REFER to Supplemental Restraint System . No INSTALL a new TED. REFER to Seat Backrest Thermo-Electric Device . CLEAR the DTCs. REPEAT the self-test. DISCONNECT the battery ground cable. CONNECT passenger seat side airbag C3052. REPOWER the SRS. REFER to Supplemental Restraint System . - Measure the resistance between passenger seat backrest TED C3039 pin 5 and pin 8, component side. Note the ambient temperature and refer to the following table.
- AS18 CHECK THE PASSENGER SEAT BACKREST TED HEATING/COOLING CIRCUITRY CURRENT DRAW
- Connect: All Front Seat Climate Control Module (SCME), TED and Body Harness-to-Seat Harness Connectors.
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NOTE: It may be necessary to open the seat wire harness conduit to allow placing the inductive current probe around the circuit as described in the following step. Care must be taken when opening up the wire harness so as not to damage any wiring or connectors. Do not damage any wiring or induce stress on any wiring or connectors. Close up the wire harness once repairs to the seat are complete.NOTE: Use a commercially available inductive current probe (such as Electronic Specialties Current Probe/Multimeter 685 or a Fluke I410 [used with a digital multimeter]) or the low current probe from the Vehicle Measurement Module available for use with IDS. If these are unavailable, the inductive current probe feature from a battery tester may be substituted.
Place an inductive current probe around circuit CHS06 (BU/BN) near Front Seat Climate Control Module (SCME) C3265A-C and monitor the current draw.
- Start the vehicle and set the passenger seat to HIGH heat.
Is the current draw less than 11 amps?
Yes GO to AS19. No INSTALL a new passenger seat backrest TED. REFER to Seat Backrest Thermo-Electric Device . CLEAR the DTCs. REPEAT the self-test. DISCONNECT the battery ground cable. CONNECT passenger seat side airbag C3052. REPOWER the SRS. REFER to Supplemental Restraint System . - AS19 CHECK RESISTANCE OF THE PASSENGER SEAT BACKREST TED AND WIRING
- Ignition OFF.
- Disconnect: Front Seat Climate Control Module (SCME) C3265A.
- Measure the resistance between Front Seat Climate Control Module (SCME) C3265A-C circuit CHS06 (BU/BN), harness side and C3265A-D , circuit RHS06 (WH), harness side.
Is the resistance between 0.9 and 10 ohms?
Yes GO to AS21. No GO to AS20. - AS20 CHECK THE RESISTANCE OF THE PASSENGER SEAT BACKREST TED
- Disconnect: Passenger Seat Backrest TED C3039.
- Measure the resistance between passenger seat backrest TED C3039 pin 1 and pin 3, component side.
Is the resistance between 0.9 and 10 ohms?
Yes REPAIR circuit CHS01 (GY/VT)/CHS06 (BU/BN) or RHS01 (WH/VT)/RHS06 (WH) for an open or high resistance. CLEAR the DTCs. REPEAT the self-test. DISCONNECT the battery ground cable. CONNECT passenger seat side airbag C3052. REPOWER the SRS. REFER to Supplemental Restraint System . No INSTALL a new passenger seat backrest TED. REFER to Seat Backrest Thermo-Electric Device . CLEAR the DTCs. REPEAT the self-test. DISCONNECT the battery ground cable. CONNECT passenger seat side airbag C3052. REPOWER the SRS. REFER to Supplemental Restraint System . - AS21 CHECK FOR CORRECT Front Seat Climate Control Module (SCME) OPERATION
- Inspect the Front Seat Climate Control Module (SCME) and passenger seat backrest TED harness and component side connectors and the body harness-to-seat harness connectors for:
- corrosion
- damaged pins
- pushed-out pins
- Connect: All Front Seat Climate Control Module (SCME), TED and Body Harness-to-Seat Harness Connectors.
- Make sure the connectors are seated correctly.
- Start the engine.
- Set the passenger seat to OFF.
- Enter the following diagnostic mode on the scan tool: Clear DTCs - Front Seat Climate Control Module (SCME).
- Attempt to recreate the fault. With the engine still running set the passenger seat to HIGH heat for at least 15 minutes.
Is the concern still present?
Yes INSTALL a new Front Seat Climate Control Module (SCME). REFER to Dual Climate Controlled Seat Module (DCSM) . REPEAT the self-test. TEST the system for normal operation. DISCONNECT the battery ground cable. CONNECT passenger seat side airbag C3052. REPOWER the SRS. REFER to Supplemental Restraint System . No The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. DISCONNECT the battery ground cable. CONNECT passenger seat side airbag C3052. REPOWER the SRS. REFER to Supplemental Restraint System . - Inspect the Front Seat Climate Control Module (SCME) and passenger seat backrest TED harness and component side connectors and the body harness-to-seat harness connectors for: