B135C:11
Heated Steering Wheel
Pinpoint Test D: DTC B135C:11 or B135C:15
Refer to Wiring Diagram Set 128, Adjustable Steering Column for schematic and connector information Electrical Diagrams.
Normal Operation
When steering wheel heat is requested, the Heated Steering Wheel Module (HSWM) applies voltage and ground to the steering wheel heating element (integral to the steering wheel). The steering wheel heating element will draw between 1 and 10A of current depending on steering wheel temperature. The steering wheel contains 3 heating elements wired in parallel and has a resistance of 1.6-2.6 ohms. If the steering wheel is equipped with wood inserts, the steering wheel contains 2 heating elements wired in parallel and has a resistance of 2.1-3.1 ohms. The heated steering wheel temperature is maintained by the HSWM (Heated Steering Wheel Module) using a sensor in the steering wheel (integral to the steering wheel). The HSWM (Heated Steering Wheel Module) is designed to remain on, heating the steering wheel and maintaining temperature until switched OFF on the Front Display Interface Module (FDIM) or the ignition is turned OFF.
- DTC B135C:11 (Heater Element: Circuit Short to Ground)- This DTC will only set when the heated steering wheel is commanded on. The module senses current greater than 10A on the steering wheel heating element output circuit for greater than 80ms, indicating a short to ground, this DTC sets. This DTC also sets when the steering wheel heating element output Field-Effect Transistor (FET) in the module has a thermal failure. The steering wheel heating element output will be disabled until the ignition is cycled.
- DTC B135C:15 (Heater Element: Circuit Short to Battery or Open)- This DTC will only set when the heated steering wheel is commanded on. The module senses current less than 1A on the steering wheel heating element output circuit for more than 80ms, indicating a short to voltage or an open circuit or heating element. The steering wheel heating element output will be disabled until the ignition is cycled.
This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Steering wheel
- Clockspring
- HSWM (Heated Steering Wheel Module)
PINPOINT TEST D : DTC B135C:11 OR B135C:15
D1 CHECK THE HSWM (Heated Steering Wheel Module) DTCs
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: Self-Test- HSWM (Heated Steering Wheel Module).
Is DTC B135C:11 present?
Yes
GO to D2.
No
For DTC B135C:15, GO to D5.
For all other DTCs, REFER to the Heated Steering Wheel Module (HSWM) DTC Chart Steering Wheel.
D2 CHECK THE HEATER ELEMENT VOLTAGE CIRCUIT FOR A SHORT TO GROUND
- Ignition OFF.
- Disconnect: HSWM (Heated Steering Wheel Module) C2406.
- Measure the resistance between ground and HSWM (Heated Steering Wheel Module) C2406-8, circuit CHS72 (YE/BU), harness side.
Is the resistance greater than 10,000 ohms?
Yes
GO to D6.
No
GO to D3.
D3 CHECK THE HEATER ELEMENT VOLTAGE CIRCUIT FOR A SHORT TO GROUND
- Remove the steering column shrouds to access the clockspring connectors. Refer to Steering Column Shroud .
- Disconnect: Clockspring C218D.
- Measure the resistance between ground and HSWM (Heated Steering Wheel Module) C2406-8, circuit CHS72 (YE/BU), harness side.
Is the resistance greater than 10,000 ohms?
Yes
GO to D4.
No
REPAIR circuit CHS72 (YE/BU) for a short to ground. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
D4 CHECK THE HEATER ELEMENT FOR A SHORT TO GROUND
- Remove the driver air bag module.
- Disconnect: Clockspring C218E.
- Measure the resistance between ground and clockspring C218E-1, harness side.
Is the resistance greater than 10,000 ohms?
Yes
INSTALL a new clockspring. REINSTALL the driver air bag module. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
No
INSTALL a new steering wheel. REFER to Steering Wheel . REINSTALL the driver air bag module. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
D5 CHECK THE HEATER ELEMENT VOLTAGE AND GROUND CIRCUIT FOR A SHORT TO VOLTAGE
- Ignition OFF.
- Remove the steering column shrouds to access the clockspring connectors. Refer to Steering Column Shroud .
- Disconnect: Clockspring C218D.
- Disconnect: HSWM (Heated Steering Wheel Module) C2406.
- Ignition ON.
- Measure the voltage between ground and:
- HSWM (Heated Steering Wheel Module) C2406-8, circuit CHS72 (YE/BU), harness side.
- HSWM (Heated Steering Wheel Module) C2406-7, circuit RHS72 (YE/GY), harness side.
Is any voltage present?
Yes
REPAIR circuit CHS72 (YE/BU) or RHS72 (YE/GY) for a short to voltage. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
No
GO to D6.
D6 CHECK THE HEATER ELEMENT AND CIRCUIT RESISTANCE
- Ignition OFF. (If ignition is still ON from previous step)
- Connect: Clockspring C218D (If previously disconnected).
- Measure the resistance between HSWM (Heated Steering Wheel Module) C2406-7, circuit RHS72 (YE/GY), harness side and HSWM (Heated Steering Wheel Module) C2406-8, circuit CHS72 (YE/BU), harness side.
Is the resistance between 1.6 and 3.1 ohms?
Yes
GO to D10.
No
If the resistance is less than 1.6 ohms, GO to D7.
If the resistance is more than 3.1 ohms, GO to D8.
D7 CHECK THE HEATER ELEMENT CIRCUITS FOR A SHORT
- Disconnect: Clockspring C218D.
- Measure the resistance between HSWM (Heated Steering Wheel Module) C2406-7, circuit RHS72 (YE/GY), harness side and HSWM (Heated Steering Wheel Module) C2406-8, circuit CHS72 (YE/BU), harness side.
Is the resistance greater than 10,000 ohms?
Yes
GO to D9.
No
REPAIR circuit CHS72 (YE/BU) and RHS72 (YE/GY) for a short together. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
D8 CHECK THE HEATER ELEMENT CIRCUITS FOR AN OPEN
- Disconnect: Clockspring C218D.
- Measure the resistance between HSWM (Heated Steering Wheel Module) C2406-7, circuit RHS72 (YE/GY), harness side and C218D-2, circuit RHS72 (YE/GY), harness side.
- Measure the resistance between HSWM (Heated Steering Wheel Module) C2406-8, circuit CHS72 (YE/BU), harness side and clockspring C218D-1, circuit CHS72 (YE/BU), harness side.
Are the resistances less than 5 ohms?
Yes
GO to D9.
No
REPAIR circuit CHS72 (YE/BU) or RHS72 (YE/GY) for an open. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
D9 CHECK THE HEATER ELEMENT RESISTANCE
- Remove the driver air bag module.
- Disconnect: Clockspring C218E.
- Measure the resistance between clockspring C218E-1, steering wheel side and clockspring C218E-2, steering wheel side.
Is the resistance between 1.6 and 3.1 ohms?
Yes
INSTALL a new clockspring. REINSTALL the driver air bag module. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
No
INSTALL a new steering wheel. REFER to Steering Wheel . REINSTALL the driver air bag module. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
D10 CHECK THE HSWM (Heated Steering Wheel Module) CONNECTION
- Disconnect all the HSWM (Heated Steering Wheel Module) connectors.
- Inspect the HSWM (Heated Steering Wheel Module) connectors for:
- corrosion
- pushed-out terminals
- damaged terminals
- Connect and correctly seat all the HSWM (Heated Steering Wheel Module) connectors.
- Ignition ON.
- Clear the DTCs.
- Enter the following diagnostic mode on the scan tool: Self-Test- Heated Steering Wheel Module (HSWM).
- Operate the heated steering wheel system and verify the concern is still present.
Is the concern still present?
Yes
INSTALL a new HSWM (Heated Steering Wheel Module). REFER to Heated Steering Wheel Module (HSWM) . TEST the system for normal operation.
No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. TEST the system for normal operation.