C0870

Circuit Description
The suspension control module provides a common regulated voltage of approximately 5 volts to all four of the (body-to-wheel) position sensors, RTD air pressure sensor and the steering hand wheel position/speed sensor. The suspension control module monitors this reference voltage for any malfunctions that could prevent it from outputting a regulated 5 volts.
For a full system schematic refer to: Suspension Controls Schematics.


Conditions for Running the DTC
Continuously with the ignition on.


Conditions for Setting the DTC
The suspension control module senses a sensor reference voltage of less than 4.0 volts or greater than 6.0 volts.


Action Taken When the DTC Sets
^ DTC C0870 will be stored in memory.
^ Disable all EVO outputs.
^ Disable all compressor leveling functions, and assume default pressure.
^ Disable all shock solenoid valve outputs.
^ The SERVICE RIDE CONTROL message will be displayed.


Conditions for Clearing the MIL/DTC
^ The suspension control module senses the correct voltage output to the position sensors upon the next ignition cycle.
^ A history DTC will clear after not seeing the malfunction for 100 consecutive ignition cycles.
^ Using a scan tool.


Diagnostic Aids
^ The following conditions may cause a malfunction to occur:
^ A short to voltage in any one of the (body-to-wheel) position sensor reference voltage circuit.
^ A short to ground in any one of the (body-to-wheel) position sensor reference voltage circuit.
^ If the circuit is shorted to ground the scan tool will display all position sensor voltage as zero.
^ If the circuit is shorted to a unwanted voltage source, the scan tool may display all position sensor voltage as that voltage.
^ A short to voltage in the 5 volt reference of the RTD air pressure sensor.
^ A short to ground in the 5 volt reference of the RTD air pressure sensor.
^ A short to voltage in the 5 volt reference of the steering hand wheel position/speed sensor.
^ A short to ground in the 5 volt reference of the steering hand wheel position/speed sensor.
^ A intermittent malfunction or DTC may cause a random firm/soft ride condition.


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 whether the condition has been corrected or identified as specified in the supporting text.
5. Tests all position sensors reference voltage circuits.
6. Tests the 5 volt reference circuit of the steering hand wheel position/speed sensor for a short to ground and a short to voltage.
7. Tests the 5 volt reference circuit of the RTD air pressure sensor for a short to ground and a short to voltage.
8. Clear DTCs and checks to see if DTC will reset.