DTC C0900 PSCM
Diagnostic Instructions
| • | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
| • | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
| • | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
DTC Descriptor
DTC C0900 00: Device Voltage High - PSCMDiagnostic Fault Information
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
|---|---|---|---|---|
B+ | C0899 00 | C0899 00 | -- | -- |
Ground | -- | C0899 00 | -- | -- |
Typical Scan Tool Data
Circuit | Short to Ground | Open | Short to Voltage |
|---|---|---|---|
Operating Conditions: Ignition ON, Engine OFF. Parameter Normal Value: 12.60 Volts | |||
B+ | 0.00 Volts | 0.00 Volts | 12.60 Volts |
Circuit/System Description
The power steering control module (PSCM) monitors the amount of battery voltage available to it. If the voltage is too high, then the PSCM sets DTC C0900 00 and disables itself in order to protect itself against high voltage damage.
Conditions for Running the DTC
The ignition is ON.
Conditions for Setting the DTC
Power steering system voltage is greater than 16 volts for 1 second.
Action Taken When the DTC Sets
| • | The PSCM is disabled. |
| • | No steering assist is provided. |
| • | The driver information center (DIC) displays the POWER STEERING message. |
Conditions for Clearing the DTC
| • | A current DTC will clear when the power steering system voltage returns to less than 16 volts. |
| • | A history DTC will clear after 100 consecutive ignition cycles from when power steering system voltage is less than 16 volts. |
Diagnostic Aids
| • | A possible cause of this DTC could be overcharging with a battery charger or jump starting. |
| • | A high voltage DTC in multiple modules indicates a concern in the charging system. |
Reference Information
Schematic Reference
Connector End View Reference
Description and Operation
Power Steering System Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Verification
- Engine running, accessories OFF, measure and record the battery voltage at the battery terminals. The voltage should be between 12.6 and 15.0 volts.
- Observe the scan tool PSCM Battery Voltage Signal parameter. The reading should be between 12.6 and 15.0 volts.
| ⇒ | If not within the specified range, refer to Charging System Test. |
| ⇒ | If not within the specified range, replace the PSCM. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
Control Module References for PSCM replacement, setup, and programming.
DTC C0900 EBCM
Diagnostic Instructions
| • | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
| • | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
| • | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
DTC Descriptor
DTC C0900 00: Device Voltage High - EBCMDiagnostic Fault Information
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
|---|---|---|---|---|
B+ | C0899 00 | C0899 00 | -- | -- |
Ground | -- | C0899 00 | -- | -- |
Typical Scan Tool Data
Circuit | Short to Ground | Open | Short to Voltage |
|---|---|---|---|
Operating Conditions: Ignition ON, engine OFF. Parameter Normal Value: 12.60 Volts | |||
B+ | 0.00 Volts* | 0.00 Volts* | 12.60 Volts |
Ground | 12.60 Volts | 0.00 Volts* | -- |
*The scan tool will not communicate with the EBCM if there is 0 Volts on the circuit. | |||
Circuit/System Description
The electronic brake control module (EBCM) monitors the ignition voltage. If the voltage level is too high, damage may result in the system. When a high voltage condition is detected the EBCM turns OFF the system relay which removes battery voltage from the solenoid valves and pump motor.
Conditions for Running the DTC
The ignition is ON.
Conditions for Setting the DTC
The EBCM detects that the battery voltage is greater than 16 volts (w/o HP7) or 17 volts (HP7).
Action Taken When the DTC Sets
| • | The antilock brake system (ABS) is disabled. (HP7) |
| • | The dynamic rear proportioning (DRP) defaults to hold only. (HP7) |
| • | The ABS and DRP are disabled, if the battery voltage is greater than 19.5 volts. (w/o HP7) |
| • | The vehicle stability enhancement system (VSES) is disabled, if equipped. |
| • | The hydraulic brake assist (HBA) and traction control system (TCS) are disabled. (w/o HP7) |
| • | The TCS is reduced to engine torque reduction only. (HP7) |
| • | The ABS indicator turns ON. (HP7) |
| • | The ABS indicator turns ON, if the battery voltage is greater than 19.5 volts. (w/o HP7) |
| • | The BRAKE and VDC indicators turn ON. |
| • | The driver information center (DIC) displays the ESC OFF message 1 time, if equipped. |
| • | The DIC displays the SERVICE ESC message, if equipped. |
| • | The DIC displays the SERVICE TRACTION message. |
Conditions for Clearing the DTC
| • | The condition for the DTC is no longer present. |
| • | The EBCM automatically clears the history DTC when a current DTC is not detected in 100 consecutive drive cycles. |
| • | The indicators and DIC messages turn OFF when the DTC passes. |
Diagnostic Aids
| • | A possible cause of this DTC could be overcharging with a battery charger or jump starting. |
| • | A high voltage DTC in multiple modules indicates a concern in the charging system. |
Reference Information
Schematic Reference
Antilock Brake System Schematics
Connector End View Reference
Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Verification
- Engine running, accessories OFF, measure and record the battery voltage at the battery terminals. The voltage should be between 12.6 and 15.0 volts.
- Observe the scan tool EBCM Battery Voltage Signal parameter. The reading should be between 12.60 and 15.00 volts.
| ⇒ | If not within the specified range, refer to Charging System Test. |
| ⇒ | If not within the specified range, replace the EBCM. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
Control Module References for EBCM replacement, setup, and programming.
