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. |
| • | Review Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
DTC Descriptors
DTC C1106 00: Brake Fluid Pressure Hold Solenoid 1 Circuit LowDTC C1107 00: Brake Fluid Pressure Hold Solenoid 1 Circuit High
DTC C1109 00: Brake Fluid Pressure Hold Solenoid 2 Circuit Low
DTC C1110 00: Brake Fluid Pressure Hold Solenoid 2 Circuit High
DTC C1111 00: Brake Fluid Pressure Hold Solenoids Enable
Diagnostic Fault Information
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
|---|---|---|---|---|
Relay Control B+ | C1106 00, C1109 00 | C1106 00, C1109 00 | -- | -- |
Relay Coil Supply Voltage | C1111 00 | C1111 00 | -- | -- |
Relay Coil Control | C1111 00 | C1111 00 | -- | -- |
Solenoid 1 Control | C1106 00 | C1106 00 | C1107 00 | -- |
Solenoid 2 Control | C1109 00 | C1109 00 | C1110 00 | -- |
Circuit/System Description
The starter generator control module (SGCM) provides a ground to the hill hold relay. The relay provides voltage circuits to the hill hold solenoid valves (HHV). The SGCM controls the HHV through a pulse width modulated circuit closing the valves and maintaining brake pressure to the brakes when stopped to prevent vehicle roll forward or backward. The SGCM will open the valves releasing the brake pressure when the engine is started.
Conditions for Running the DTC
Ignition ON.
Conditions for Setting the DTC
C1106 00, C1109 00
An open/short to ground is detected on the hill hold solenoid circuit.
C1107 00, C1110 00
A short to voltage is detected on the hill hold solenoid control circuit.
C1111 00
An open/short to ground is detected on the relay coil control circuit.
Action Taken When the DTC Sets
The hill start assist indicator will display on the instrument panel cluster (IPC).
Conditions for Clearing the DTC
| • | The condition for the DTC is no longer present. |
| • | The SGCM clears the history DTC when a current DTC is not detected in 100 consecutive drive cycles. |
Reference Information
Schematic Reference
Connector End View Reference
Description and Operation
Hill Hold Control Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Testing
- Ignition OFF, disconnect the hill hold vlvs relay.
- Ignition ON, verify that a test lamp illuminates between the ignition circuit terminal 85 and ground.
- Ignition OFF, connect a test lamp between the ignition circuit terminal 85 and the control circuit terminal 86.
- Ignition ON, verify that a test lamp illuminates ON and then OFF one time, between the ignition circuit terminal 85 and the control circuit terminal 86.
- Ignition ON, verify that a test lamp illuminates between the B+ circuit terminal 30 and ground.
- Ignition OFF, disconnect the harness connector at the hill hold valve.
- Connect a test lamp between B+ and the control circuit terminal 2.
- Command the SGCM Brake Hold Solenoid 1 and Brake ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states.
- Connect a test lamp between B+ and the control circuit terminal 4.
- Command the SGCM Brake Hold Solenoid 2 and Brake ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states.
- If all circuits test normal, test or replace the hill hold brake delay valve.
| ⇒ | If the test lamp does not illuminate, test the ignition circuit for a short to ground or an open/high resistance. If the circuit tests normal and the ignition circuit fuse is open, test or replace the hill hold relay. |
| ⇒ | If the test lamp is always ON, test the control circuit for a short to ground. If the circuit tests normal, replace the SGCM. |
| ⇒ | If the test lamp is always OFF, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the SGCM. |
| ⇒ | If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance. If the circuit tests normal and the B+ circuit fuse is open, test the control circuit terminal 87 for a short to ground. |
| ⇒ | If the test lamp is always ON, test the control circuit for a short to ground. If the circuit tests normal, replace the SGCM. |
| ⇒ | If the test lamp is always OFF, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the SGCM. |
| ⇒ | If the test lamp is always ON, test the control circuit for a short to ground. If the circuit tests normal, replace the SGCM. |
| ⇒ | If the test lamp is always OFF, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the SGCM. |
Component Testing
- Ignition OFF, disconnect the Hill Hold relay.
- Test for 60-180 ohms between terminals 85 and 86.
- Test for infinite resistance between the following terminals:
- Install a 30A fused jumper wire between relay terminal 85 and B+. Install a jumper wire between relay terminal 86 and ground.
- Test for less than 2 ohms between terminals 30 and 87.
| ⇒ | If the resistance is not within the specified range, replace the relay. |
| • | 30 and 86 |
| • | 30 and 87 |
| • | 30 and 85 |
| • | 85 and 87 |
| ⇒ | If not the specified value, replace the relay. |
| ⇒ | If greater than the specified range, replace the relay. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Control Module References for SGCM replacement, setup, and programming |
