C0495 - Without Real Time Dampening (RTD)

Circuit Description
The body control module supplies a Pulse Width Modulated (PWM) voltage to the Electronic Variable Orifice (EVO) solenoid as well as a low reference path. The PWM voltage is used to control the current into the solenoid which controls the size of the output orifice of the power steering pump. This results in an increase or decrease in steering wheel turning effort. The body control module is constantly adjusting the PWM voltage and monitoring the current flow to achieve the desired PWM.
The system uses inputs from VSS and the steering wheel position/speed sensor for the desired PWM output. This provides the vehicle speed related steering assist.


Conditions for Running the DTC
Vehicle speed greater than 8 km/h (5 mph). EVO solenoid command greater than 5% PWM duty cycle.


Conditions for Setting the DTC
- EVO output PWM less than 10% duty cycle and EVO output current greater than 260 mA. or
- EVO output PWM greater than 94% duty cycle and EVO output current less than or equal to 360 mA.


Action Taken When the DTC Sets
- DTC C0495 will be stored in memory.
- The body control module will turn off both EVO solenoid outputs for the remainder of the ignition cycle.


Conditions for Clearing the MIL/DTC
- A history DTC will clear after not seeing the malfunction for 100 consecutive ignition cycles.
- Using a scan tool to clear the DTC.


Diagnostic Aids
- Perform a visual inspection for loose or poor connections at all related components.
- Refer to Testing for Intermittent and Poor Connections in Diagrams/Diagnostic Aids.

Important:
- An EVO solenoid that is out of resistance range may cause this DTC to set.
- Normal resistance of the EVO solenoid is from 11 to 13 ohms.

- Low vehicle speed = high level of assist.
- High vehicle speed = low level of assist.
- EVO is controlled by the body control module on vehicles without the Z55 RPO option.
- Vehicles with the Z55 RPO option utilize the suspension control module to control the EVO.


Test Description
The number(s) below refer to the step number(s) on the diagnostic table.
3. Tests whether the condition is module, system, or condition related.
4. Tests the resistance of the EVO solenoid.
5. Tests the EVO circuits.
7. Clear DTCs and check if the DTC resets.