Pinpoint Test K: The Heated Seat Is Inoperative - Driver
Seats
Pinpoint Tests
Pinpoint Test K: The Heated Seat is Inoperative - Driver
Refer to Wiring Diagram Set 119, Climate Controlled Seats for schematic and connector information. Diagrams By Number
Normal Operation
The heated seat module is supplied battery and switched ignition voltage. The heated seat is activated when the heated seat switch supplies a ground signal to one of 2 input circuits into the heated seat module. One circuit activates the system to hi or off. The other circuit activates the system to low or off. Once activated, the heated seat module supplies voltage and ground to the heater mat to heat the seat cushion and backrest. The heated seat module monitors the temperature sensor in the cushion heater mat to maintain the seat temperature. The system will remain on until the module times-out or is switched off.
This pinpoint test is intended to diagnose the following:
- Fuse(s)
- Wiring, terminals or connectors
- Heated seat switch
- Heater mat
- Heated seat module
PINPOINT TEST K: THE HEATED SEAT IS INOPERATIVE - DRIVER
WARNING: Remove restraint system diagnostic tools from the vehicle prior to road testing. If tools are not removed, the supplemental restraint system (SRS) device may not deploy in a crash. Failure to follow this instruction may result in serious personal injury or death in a crash and possibly violate vehicle safety standards.
NOTICE: Use the correct probe adapter(s) from the Flex Probe Kit when making measurements. Failure to use the correct probe adapter(s) may damage the connector.
NOTICE: Most faults are due to connector and/or wiring concerns. Carry out a thorough inspection and verification before proceeding with the pinpoint test. Inspection and Verification
NOTE: The SRS must be fully operational and free of faults before releasing the vehicle to the customer.
NOTE: If a driver seat heater mat (cushion or backrest) is faulty, a new foam pad must be installed with the new heater mat. Do not reuse the original foam pad.
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K1 CHECK HEATED SEAT SWITCH AND CIRCUIT RESISTANCE
- Ignition OFF.
- Depower the Supplemental Restraint System (SRS). Refer to Supplemental Restraint System (SRS) Depowering and Repowering in the General Procedures portion of Supplemental Restraint System Supplemental Restraint System (SRS) Depowering and Repowering.
- Disconnect: Driver Seat Side Air Bag C315.
- Connect: Restraint System Diagnostic Service Tool to Driver Seat Side Air Bag C315.
- Disconnect: Driver Heated Seat Module C359.
- Measure resistance between:
- driver heated seat module C359-8, circuit 1020 (DG/VT), harness side and ground while pressing the heated seat switch.
- driver heated seat module C359-11, circuit 1255 (WH/RD), harness side and ground while pressing the heated seat switch.
- Are the resistances less than 50 ohms when the heated seat switch is pressed and greater than 10,000 ohms when the heated seat switch is not pressed?
Yes
GO to K3.
No
GO to K2.
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K2 CHECK THE DRIVER HEATED SWITCH GROUND CIRCUIT FOR AN OPEN
- Disconnect: Driver Heated Seat Switch C538.
- Measure resistance between driver heated seat switch C538-1, circuit 57 (BK), harness side and ground.
- Is the resistance less than 5 ohms?
Yes
INSTALL a new heated seat switch. REFER to Heated Seat Switch Heated Seat Switch. TEST the system for normal operation.
DISCONNECT the battery ground cable. DISCONNECT the restraint system diagnostic service tool from driver seat side air bag module C315. CONNECT driver seat side air bag module C315. REPOWER the SRS. REFER to Supplemental Restraint System Supplemental Restraint System (SRS) Depowering and Repowering.
No
REPAIR the circuit. TEST the system for normal operation.
DISCONNECT the battery ground cable. DISCONNECT the restraint system diagnostic service tool from driver seat side air bag module C315. CONNECT driver seat side air bag module C315. REPOWER the SRS. REFER to Supplemental Restraint System Supplemental Restraint System (SRS) Depowering and Repowering.
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K3 CHECK FOR VOLTAGE TO THE HEATED SEAT MODULE
- Ignition OFF.
- WARNING: Make sure no one is in the vehicle and there is nothing blocking or placed in front of any air bag module 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 Battery Disconnect.
- Measure voltage between driver heated seat module C359-12, circuit 1048 (LB/WH), harness side and ground.
- Is the voltage greater than 10 volts?
Yes
GO to K4.
No
VERIFY the Battery Junction Box (BJB) fuse 16 (20A) is OK. If OK, REPAIR the circuit. If not OK, REFER to the Wiring Diagrams to identify the possible causes of the circuit short. TEST the system for normal operation. Diagrams By Number
DISCONNECT the battery ground cable. DISCONNECT the restraint system diagnostic service tool from driver seat side air bag module C315. CONNECT driver seat side air bag module C315. REPOWER the SRS. REFER to Supplemental Restraint System Supplemental Restraint System (SRS) Depowering and Repowering.
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K4 CHECK FOR VOLTAGE TO THE HEATED SEAT MODULE
- Ignition ON.
- Measure voltage between driver heated seat module C359-5, circuit 1040 (RD/BK), harness side and ground.
- Is the voltage greater than 10 volts?
Yes
GO to K5.
No
VERIFY the Central Junction Box (CJB) fuse 17 (10A) is OK. If OK, REPAIR the circuit. If not OK, REFER to the Wiring Diagrams to identify the possible causes of the circuit short. TEST the system for normal operation. Diagrams By Number
DISCONNECT the battery ground cable. DISCONNECT the restraint system diagnostic service tool from driver seat side air bag module C315. CONNECT driver seat side air bag module C315. REPOWER the SRS. REFER to Supplemental Restraint System Supplemental Restraint System (SRS) Depowering and Repowering.
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K5 CHECK THE DRIVER HEATED SEAT MODULE GROUND CIRCUIT FOR AN OPEN
- Ignition OFF.
- Measure resistance between driver heated seat module C359-1, circuit 57 (BK), harness side and ground.
- Is the resistance less than 5 ohms?
Yes
GO to K6.
No
REPAIR the circuit. TEST the system for normal operation.
DISCONNECT the battery ground cable. DISCONNECT the restraint system diagnostic service tool from driver seat side air bag module C315. CONNECT driver seat side air bag module C315. REPOWER the SRS. REFER to Supplemental Restraint System Supplemental Restraint System (SRS) Depowering and Repowering.
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K6 CHECK HEATER CIRCUIT RESISTANCE AND FOR A SHORT TO GROUND
- Measure resistance between:
- driver heated seat module C359-6, circuit 1064 (YE/LB), harness side and C359-7, circuit 1065 (WH/LB), harness side.
- driver heated seat module C359-6, circuit 1064 (YE/LB), harness side and ground.
- Is the resistance between 1.6 ohms and 10 ohms between C359-6 and C359-7 and greater than 10,000 ohms between the C359-6 and ground?
Yes
GO to K7.
No
GO to K12.
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K7 CHECK HEATERS AND CIRCUITS FOR A SHORT TO VOLTAGE
- Ignition ON.
- Measure voltage between:
- driver heated seat module C359-6, circuit 1064 (YE/LB), harness side and ground.
- driver heated seat module C359-7, circuit 1065 (WH/LB), harness side and ground.
- Is voltage present on either circuit?
Yes
REPAIR the circuit(s). TEST the system for normal operation.
DISCONNECT the battery ground cable. DISCONNECT the restraint system diagnostic service tool from driver seat side air bag module C315. CONNECT driver seat side air bag module C315. REPOWER the SRS. REFER to Supplemental Restraint System Supplemental Restraint System (SRS) Depowering and Repowering.
No
GO to K8.
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K8 CHECK THE TEMPERATURE SENSOR AND CIRCUITS FOR A SHORT TO VOLTAGE
- Measure voltage between:
- driver heated seat module C359-3, circuit 1061 (BN/LB), harness side and ground.
- driver heated seat module C359-4, circuit 1060 (BK/LB), harness side and ground.
- Is voltage present on either circuit?
Yes
REPAIR the circuit(s). TEST the system for normal operation.
DISCONNECT the battery ground cable. DISCONNECT the restraint system diagnostic service tool from driver seat side air bag module C315. CONNECT driver seat side air bag module C315. REPOWER the SRS. REFER to Supplemental Restraint System Supplemental Restraint System (SRS) Depowering and Repowering.
No
GO to K9.
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K9 CHECK THE TEMPERATURE SENSOR CIRCUITS RESISTANCE AND FOR A SHORT TO GROUND
- Ignition OFF.
- Measure resistance between:
- driver heated seat module C359-3, circuit 1061 (BN/LB), harness side and C359-4, circuit 1060 (BK/LB), harness side.
- driver heated seat module C359-3, circuit 1061 (BN/LB), harness side and ground.
- Is the resistance between 50 ohms and 300,000 ohms between C359-3 and C359-4 and greater than 10,000 ohms between C359-3 and ground?
Yes
INSTALL a new driver heated seat module. REFER to Heated Seat Module Heated Seat Module. TEST the system for normal operation.
DISCONNECT the battery ground cable. DISCONNECT the restraint system diagnostic service tool from driver seat side air bag module C315. CONNECT driver seat side air bag module C315. REPOWER the SRS. REFER to Supplemental Restraint System Supplemental Restraint System (SRS) Depowering and Repowering.
No
GO to K10.
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K10 CHECK THE SENSOR RETURN CIRCUIT FOR AN OPEN OR SHORT TO GROUND
- Disconnect: Driver Seat Cushion Heater C364.
- Measure resistance between:
- driver heated seat module C359-3, circuit 1061 (BN/LB), harness side and driver seat cushion heater C364-2, circuit 1061 (BN/LB), harness side.
- driver heated seat module C359-3, circuit 1061 (BN/LB), harness side and ground.
- Is the resistance less than 5 ohms between the heated seat module and seat cushion heater and greater than 10,000 ohms between the heated seat module and ground?
Yes
GO to K11.
No
REPAIR the circuit. TEST the system for normal operation.
DISCONNECT the battery ground cable. DISCONNECT the restraint system diagnostic service tool from driver seat side air bag module C315. CONNECT driver seat side air bag module C315. REPOWER the SRS. REFER to Supplemental Restraint System Supplemental Restraint System (SRS) Depowering and Repowering.
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K11 CHECK THE SENSOR CIRCUIT FOR AN OPEN OR SHORT TO GROUND
- Measure resistance between:
- driver heated seat module C359-4, circuit 1060 (BK/LB), harness side and driver seat cushion heater C364-3, circuit 1060 (BK/LB), harness side.
- driver heated seat module C359-4, circuit 1060 (BK/LB), harness side and ground.
- Is the resistance less than 5 ohms between the heated seat module and seat cushion heater and greater than 10,000 ohms between the heated seat module and ground?
Yes
INSTALL a new driver seat cushion heater. TEST the system for normal operation.
DISCONNECT the battery ground cable. DISCONNECT the restraint system diagnostic service tool from driver seat side air bag module C315. CONNECT driver seat side air bag module C315. REPOWER the SRS. REFER to Supplemental Restraint System Supplemental Restraint System (SRS) Depowering and Repowering.
No
REPAIR the circuit. TEST the system for normal operation.
DISCONNECT the battery ground cable. DISCONNECT the restraint system diagnostic service tool from driver seat side air bag module C315. CONNECT driver seat side air bag module C315. REPOWER the SRS. REFER to Supplemental Restraint System Supplemental Restraint System (SRS) Depowering and Repowering.
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K12 CHECK THE HEATER POWER FEED CIRCUIT FOR AN OPEN OR SHORT TO GROUND
- Disconnect: Driver Seat Cushion Heater C364.
- Measure resistance between:
- driver heated seat module C359-6, circuit 1064 (YE/LB), harness side and driver seat cushion heater C364-4, circuit 1064 (YE/LB), harness side.
- driver heated seat module C359-6, circuit 1064 (YE/LB), harness side and ground.
- Is the resistance less than 5 ohms between the heated seat module and seat cushion heater and greater than 10,000 ohms between the heated seat module and ground?
Yes
GO to K13.
No
REPAIR the circuit. TEST the system for normal operation.
DISCONNECT the battery ground cable. DISCONNECT the restraint system diagnostic service tool from driver seat side air bag module C315. CONNECT driver seat side air bag module C315. REPOWER the SRS. REFER to Supplemental Restraint System Supplemental Restraint System (SRS) Depowering and Repowering.
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K13 CHECK THE HEATER RETURN FEED CIRCUIT FOR AN OPEN OR SHORT TO GROUND
- Measure resistance between:
- driver heated seat module C359-7, circuit 1065 (WH/LB), harness side and driver seat cushion heater C364-1, circuit 1065 (WH/LB), harness side.
- driver heated seat module C359-7, circuit 1065 (WH/LB), harness side and ground.
- Is the resistance less than 5 ohms between the heated seat module and seat cushion heater and greater than 10,000 ohms between the heated seat module and ground?
Yes
GO to K14.
No
REPAIR the circuit. TEST the system for normal operation.
DISCONNECT the battery ground cable. DISCONNECT the restraint system diagnostic service tool from driver seat side air bag module C315. CONNECT driver seat side air bag module C315. REPOWER the SRS. REFER to Supplemental Restraint System Supplemental Restraint System (SRS) Depowering and Repowering.
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K14 CHECK THE SEAT BACK HEATER RESISTANCE
- Disconnect: Driver Seat Back Heater C365.
- Measure resistance between driver seat back heater C365 pin 1 and pin 2, component side.
- Is the resistance between 0.6 and 0.9 ohm?
Yes
INSTALL a new driver seat cushion heater. TEST the system for normal operation.
DISCONNECT the battery ground cable. DISCONNECT the restraint system diagnostic service tool from driver seat side air bag module C315. CONNECT driver seat side air bag module C315. REPOWER the SRS. REFER to Supplemental Restraint System Supplemental Restraint System (SRS) Depowering and Repowering.
No
INSTALL a new driver seat back heater. TEST the system for normal operation.
DISCONNECT the battery ground cable. DISCONNECT the restraint system diagnostic service tool from driver seat side air bag module C315. CONNECT driver seat side air bag module C315. REPOWER the SRS. REFER to Supplemental Restraint System Supplemental Restraint System (SRS) Depowering and Repowering.
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