DTC P2796-P2799

Automatic Transmission - 10L80 MHS MQC | Diagnostic Information and Procedures | Document ID: 5224836 Diagnostic Instructions Perform the Diagnostic System Check prior to using this diagnostic procedure: Diagnostic System Check - Vehicle Review the description of Strategy Based Diagnosis: Strategy Based Diagnosis An overview of each diagnostic category can be found here: Diagnostic Procedure Instructions DTC Descriptor DTC P2796 Automatic Transmission Auxiliary Fluid Pump Control Circuit DTC P2797 Automatic Transmission Auxiliary Fluid Pump Performance DTC P2798 Automatic Transmission Auxiliary Fluid Pump Control Circuit Low DTC P2799 Automatic Transmission Auxiliary Fluid Pump Control Circuit High Diagnostic Fault Information

Circuit	Short to Ground	Open/High Resistance	Short to Voltage	Signal Performanc
B+ — Terminal 1 @ G5 Automatic Transmission Auxiliary Fluid Pump	1	P2797	—	P2797
Control — Terminal 3 @ G5 Automatic Transmission Auxiliary Fluid Pump	P0658	P0658	P0659	P2797
Control — Terminal 4 @ G5 Automatic Transmission Auxiliary Fluid Pump	P2798	P2796	P2799	P2797
Ground — Terminal 6 @ G5 Automatic Transmission Auxiliary Fluid Pump	—	P2797	1	P2797
1. Fuse — Open 2. Autostart/Autostop = Disabled — G5 Automatic Transmission Auxiliary Fluid Pump — Inoperative

Note

DTC P2797 will set with a hydraulic/mechanical condition. The components are listed from the least to the most intrusive to service.

Component	DTC	Condition
Automatic Transmission Auxiliary Fluid Pump Outlet Pipe	P2797	Incorrect installation Leaking Mechanically damaged Missing components Restricted
Automatic Transmission Auxiliary Fluid Pump Seal	P2797	Incorrect installation Leaking Mechanically damaged Missing
Automatic Transmission Auxiliary Fluid Pump Outlet Pipe Seal	P2797	Incorrect installation Leaking Mechanically damaged Missing
G5 Automatic Transmission Auxiliary Fluid Pump	P2797	Binding or Sticking Debris on the component. Mechanically damaged
Control Valve Body	P2797	Transmission Fluid Pump Check Ball — Restricted / Leaking / Mechanically damaged Fluid/oil passage — Restricted / Leaking

Circuit/System Description For an overview of the component/system, refer to: Electronic Component Description

	Circuit	Description
	B+ — Terminal 1 @ G5 Automatic Transmission Auxiliary Fluid Pump	Supplied from a fuse.
	Control — Terminal 3 @ G5 Automatic Transmission Auxiliary Fluid Pump	The output circuit is switched to 12 V to activate the component.
	Control — Terminal 4 @ G5 Automatic Transmission Auxiliary Fluid Pump	The output circuit is switched to ground to activate the component. The output is PWM controlled.

Circuit	Description
Ground — Terminal 6 @ G5 Automatic Transmission Auxiliary Fluid Pump	Chassis Ground

Component	Description
G5 Automatic Transmission Auxiliary Fluid Pump	An electric DC motor.
K71 Transmission Control Module	The control module contains a microprocessor used to process input data to control outputs. The control module receives information from a variety of sensors, switches and serial data information from other control modules. This information is used to control a combination of solenoid valves to obtain the correct line pressure, gear ratio and torque converter clutch operation.

Conditions for Running the DTC P2796, P2798, P2799 Battery Voltage = Greater than 9 V Ignition and Start Signal = 9 to 32 V Ignition and Start Switch Signal = On P2797 DTC P171A, P171B, P171C, U0101, P182E, P1915 = Not set DTCs related to the following system/component = Not Set – B13 Automatic Transmission Fluid Temperature Sensor – B14A Automatic Transmission Output Speed Sensor – B14C Automatic Transmission Input Speed Sensor – B26 Crankshaft Position Sensor – B303 Transmission Range Sensor Autostop = Active — For greater than 1.2 s Battery Voltage = Greater than 9 V Ignition and Start Signal = 9 to 32 V Ignition and Start Switch Signal = On Propulsion Active = Yes Transmission Fluid Temperature = 0 to 110°C (32 to 230°F) Transmission Range = D, L, M Frequency the DTC runs = Continuously — After the running conditions are met Conditions for Setting the DTC P2796 Control Circuit = Open/High Resistance — For greater than 1 s P2797 Input Shaft Speed Sensor = Greater than a predefined threshold — For greater than 1 s P2798 Control Circuit = Short to Ground — For greater than 1 s P2799 Control Circuit = Short to Voltage — For greater than 1 s Actions Taken When the DTC Sets DTCs listed in the DTC Descriptor category = Type B DTC Conditions for Clearing the DTC DTCs listed in the DTC Descriptor category = Type B DTC Reference Information Schematic Reference Automatic Transmission Controls Schematics Connector End View Reference Component Connector End Views Component View Reference Disassembled Views Electrical Information Reference Circuit Testing Connector Repairs Testing for Intermittent Conditions and Poor Connections Wiring Repairs DTC Type Reference Powertrain Diagnostic Trouble Code (DTC) Type Definitions Scan Tool Reference Control Module References Circuit/System Verification

1. Ignition » On / Vehicle » In Service Mode & Engine » Off
2. Verify DTC P0658, P0659 is not set. ⇒ If DTC P0658, P0659 is set Refer to: Diagnostic Trouble Code (DTC) List - Vehicle ⇓ If DTC P0658, P0659 is not set
3. Engine » Running
4. Verify the scan tool parameter: Automatic Transmission Auxiliary Fluid Pump Control Circuit High Test Status = Not Run or Okay Automatic Transmission Auxiliary Fluid Pump Control Circuit Low Test Status = Not Run or Okay Auxiliary Transmission Fluid Pump Relay Control Circuit Open Test Status = Not Run or Okay ⇒ If not the specified state Refer to: Circuit/System Testing ⇓ If the specified state
5. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data. Verify the DTC does not set. ⇒ If the DTC sets Refer to: Circuit/System Testing ⇓ If the DTC does not set
6. All OK. Circuit/System Testing

Note

It may take up to 2 min for all vehicle systems to power down before an accurate ground or low reference circuit continuity test can be performed.

1. Ignition/Vehicle & All vehicle systems » Off

Note

When the following connector is disconnected, the ignition cannot be turned off due to lack of a valid park input to the TCM. If the ignition needs to be turned off, the connector will need to be reconnected.

2. Disconnect the electrical connector: X1 @ T12 Automatic Transmission
3. Test for less than 10 Ω between the test points: Ground circuit terminal 17 @ X1 (harness side) & Ground ⇒ If 10 Ω or greater 3.1. Disconnect the ground connection: G103 3.2. Test for less than 2 Ω between the test points: Ground circuit terminal 17 @ X1 (harness side) & G103 ⇒ If 2 Ω or greater » Repair the open/high resistance in the circuit. ⇒ If less than 2 Ω » Repair the open/high resistance in the ground connection. ⇓ If less than 10 Ω
4. Ignition » On / Vehicle » In Service Mode
5. Verify a test lamp turns On between the test points: B+ circuit terminal 10 @ X1 (harness side) & Ground ⇒ If the test lamp does not turn On and the circuit fuse is OK 5.1. Remove » Test Lamp 5.2. Test for less than 2 Ω between the test points: B+ circuit terminal 10 @ X1 (harness side) & Output terminal @ X50A ⇒ If 2 Ω or greater » Repair the open/high resistance in the circuit. ⇒ If less than 2 Ω » Verify the fuse is OK and there is voltage at the fuse. ⇒ If the test lamp does not turn On and the circuit fuse is open 5.1. Remove » Test Lamp 5.2. Test for infinite resistance between the test points: B+ circuit terminal 10 @ X1 (harness side) & Ground ⇒ If less than infinite resistance » Repair the short to ground on the circuit. ⇒ If infinite resistance If infinite resistance » Replace the component: ⇓ If the test lamp turns On
6. Disconnect the electrical connector: K71 Transmission Control Module
7. Ignition » On / Vehicle » In Service Mode
8. Test for less than 1 V between the test points: Control circuit terminal 18 @ X1 (harness side) & Ground ⇒ If greater than 1 V Repair the short to voltage on the circuit. ⇓ If less than 1 V
9. Test for greater than 5 Ω between the test points: Control circuit terminal 18 @ X1 & Ground ⇒ If less than 5 Ω Repair the short to ground on the circuit. ⇓ If greater than 5 Ω
10. Test for less than 5 Ω between the test points: Control circuit terminal 18 @ X1 & The other end of the circuit ⇒ If greater than 5 Ω Repair the open/high resistance in the circuit. ⇓ If less than 5 Ω
11. Remove the component: Automatic Transmission Fluid Pan
12. Disconnect the component: G5 Automatic Transmission Auxiliary Fluid Pump
13. Connect the electrical connector: X1 @ T12 Automatic Transmission
14. Test for battery voltage between the test points: B+ circuit terminal 1 & Ground circuit terminal 3 @ G5 Automatic Transmission Auxiliary Fluid Pump ⇒ If less than battery voltage Replace the component: Automatic Transmission Wiring Harness ⇓ If battery voltage
15. Test for less than 5 Ω between the test points: Control circuit terminal 4 & The other end of the circuit ⇒ If greater than 5 Ω Replace the component: Automatic Transmission Wiring Harness ⇓ If less than 5 Ω
16. Test for less than 5 Ω between the test points: Control circuit terminal 3 & The other end of the circuit ⇒ If greater than 5 Ω Replace the component: Automatic Transmission Wiring Harness ⇓ If less than 5 Ω
17. Refer to: Diagnostic Fault Information & Verify the conditions listed in the table do not exist ⇒ If a condition exists Repair or replace as necessary ⇓ If no condition exists
18. Test or replace the component: G5 Transmission Fluid Pump - Electric/Auxiliary Repair Instructions Perform the Diagnostic Repair Verification after completing the repair: Diagnostic Repair Verification Automatic Transmission Fluid, Fluid Pan and/or Filter Replacement Automatic Transmission Wiring Harness Replacement Auxiliary Fluid Pump Removal / Auxiliary Fluid Pump Installation — G5 Automatic Transmission Auxiliary Fluid Pump Control Valve Body Replacement For control module replacement, programming, and setup refer to: Control Module References Additional Procedures Transmission Service Fast Learn Procedure — Perform only when the component/system is serviced.