P2797
DTC P2797
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions Diagnostic Procedure Instructions provides an overview of each diagnostic category.
DTC Descriptor
DTC P2797
- Auxiliary Transmission Fluid Pump Performance
Circuit/System Description
The generator control module also called the starter generator control module is comprised of the following control modules; the hybrid powertrain control module, 14 volt power module and the drive motor control module. These modules are non serviceable and are part of the generator control module.
The hybrid powertrain control module and the motor control modules share the power inverter module ignition voltage circuit, battery voltage circuits and chassis ground. The hybrid powertrain control module controls the operation of the Auxiliary transmission fluid pump through a relay. The hybrid powertrain control module compares the output shaft speed to the input shaft speed to check for slip during an autostart event. When the autosop is inhibited due to air conditioning ON the hybrid powertrain control module will pulse the auxiliary transmission fluid pump and monitor current flow from the 14 volt power module to determine operation.
Conditions for Running the DTC
* The Ignition is ON.
* The system voltage is between 9.0 and 32.0 V.
* The vehicle is in autostop mode.
Conditions for Setting the DTC
With the air condition compressor OFF, the calculated transmission slip speed is greater than 350 RPM during an autostart.
Or
With the air condition compressor ON, the 14 volt power module output current does not increase when the auxiliary transmission fluid pump is commanded on by the hybrid powertrain control module.
Action Taken When the DTC Sets
DTC P2797 is a Type A DTC.
Conditions for Clearing the DTC
DTC P2797 is a Type A DTC.
Reference Information
Schematic Reference
Hybrid Energy Storage Schematics [1][2]Electrical Diagrams
Description and Operation
* Starter Generator Description and Operation Starter Generator Description and Operation
* Generator Control Module Description and Operation Generator Control Module Description and Operation
* Hybrid Modes of Operation Description Hybrid Modes of Operation Description
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Circuit/System Verification
1. Verify that no other hybrid powertrain or transmission control module DTC is set.
• If any hybrid powertrain or transmission control module DTC is set
Refer to Diagnostic Trouble Code (DTC) List - Vehicle Diagnostic Trouble Code (DTC) List - Vehicle.
2. Perform the Transmission Fluid Level and Condition Check 6T30/6T40/6T45/6T50 - Automatic Transmission to verify correct fluid level and condition.
3. Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the G5 Transmission Fluid Pump - Auxiliary. It may take up to 2 minutes for all vehicle systems to power down.
4. Test for less than 10 ohm between the G5 Transmission Fluid Pump - Auxiliary ground circuit X1 terminal 2 and ground.
• If 10 ohm or greater
1. Ignition OFF.
2. Test for less than 2 ohm in the ground circuit end to end.
• If 2 ohm or greater, repair the open/high resistance in the circuit.
• If less than 2 ohm, repair the open/high resistance in the ground connection.
• If less than 10 ohm
5. Connect the harness connector at the G5 Transmission Fluid Pump - Auxiliary.
6. Ignition ON, connect a 30 A fused jumper wire between the B+ circuit terminal 30 and the control circuit terminal 87.
7. Verify the G5 Transmission Fluid Pump - Auxiliary is activated.
• If the G5 Transmission Fluid Pump - Auxiliary does not activate
1. Ignition OFF.
2. Test for less than 2 ohm in the control circuit terminal 85 end to end.
• If 2 ohm or greater, repair the open/high resistance in the circuit.
• If less than 2 ohm, test or replace the G5 Transmission Fluid Pump - Auxiliary.
• If the G5 Transmission Fluid Pump - Auxiliary activates
8. Test or replace the KR86 Transmission Fluid Pump Relay - Auxiliary.
• If the DTC is set
Replace the auxiliary trans fluid pump. Refer to Auxiliary Fluid Pump Removal (Hybrid) 3. Auxiliary Fluid Pump Removal (Hybrid).
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the repair.
Auxiliary Fluid Pump Removal (Hybrid) 3. Auxiliary Fluid Pump Removal (Hybrid)