The P2797: Auxiliary Transmission Fluid Pump Performance code indicates that there are performance issues with the auxiliary transmission fluid pump. This could be caused by a faulty auxiliary pump, problems in the control circuit, or issues with wiring or connectors. The auxiliary transmission fluid pump plays a vital role in maintaining adequate transmission fluid flow, especially during low-speed or stop-start conditions to ensure proper cooling and lubrication.
P2797 – Quick Overview
| Code | Information |
|---|---|
| Meaning | P2797: Auxiliary Transmission Fluid Pump Performance |
| Is it serious? | Yes, performance issues with the auxiliary transmission fluid pump can lead to insufficient transmission fluid flow, which may result in overheating, improper lubrication, and potential damage to transmission components. |
| Possible causes | – Performance issues with the auxiliary transmission fluid pump – Faulty pump or control circuit – Wiring or connector issues |
| How to diagnose? | – Check the performance of the auxiliary transmission fluid pump – Inspect wiring and connectors – Verify control circuit operation – Replace faulty pump or components as needed |
P2797 Meaning
The P2797: Auxiliary Transmission Fluid Pump Performance code indicates that the transmission control module (TCM) has detected a performance problem with the auxiliary transmission fluid pump. This pump is essential for maintaining transmission fluid pressure and ensuring the proper cooling and lubrication of transmission components, particularly in conditions where the main pump might not be sufficient. Performance issues can result from pump failure, wiring issues, or faults in the control circuit.
Step-by-step diagnostic guide
| Action | Description | Tools Needed |
|---|---|---|
| Check for Other Codes | Use an OBD-II scanner to check if any other related codes are present. Related codes can help provide additional context regarding the specific nature of the performance issue affecting the auxiliary transmission fluid pump. | OBD-II Scanner |
| Check the Performance of the Auxiliary Transmission Fluid Pump | Start the engine and use a diagnostic tool to monitor the performance metrics of the auxiliary transmission fluid pump. Observe parameters such as fluid pressure, flow rate, and pump speed to ensure they meet manufacturer specifications. If the readings are below the recommended range, it could indicate a performance issue. | Diagnostic Tool, Manufacturer Specifications |
| Inspect Wiring and Connectors | Perform a thorough visual inspection of the wiring and connectors associated with the auxiliary transmission fluid pump. Look for damaged wires, corroded connectors, or loose connections. Poor connections can lead to intermittent pump operation or inadequate power supply, affecting pump performance. | Flashlight, Safety Gloves |
| Measure Voltage in Control Circuit | Use a multimeter to measure the voltage supplied to the auxiliary transmission fluid pump. Compare this to the manufacturer’s specifications. An insufficient voltage could cause the pump to underperform. Verify if the control module is sending the correct signal to activate the pump. | Multimeter, Manufacturer Specifications |
| Check for Relay and Fuse Issues | Verify the relay and fuse related to the auxiliary transmission fluid pump. A malfunctioning relay or blown fuse can prevent the pump from operating at full capacity, leading to performance issues. Replace any faulty relays or fuses as necessary. | Multimeter, Fuse Puller |
| Test Pump for Mechanical Problems | Inspect the auxiliary transmission fluid pump for mechanical issues. Listen for unusual noises (indicating internal damage) and check for overheating, which could indicate excessive wear or a clog. If the pump is not working efficiently, it may need to be replaced. | Stethoscope (optional), Diagnostic Tool |
| Verify Control Circuit Operation | Use a diagnostic tool to ensure the control circuit is functioning correctly. Verify the signals from the transmission control module to the auxiliary pump. Faulty control circuits can lead to inconsistent operation of the pump, affecting overall transmission fluid flow and pressure. | Diagnostic Tool, Manufacturer Software |
| Inspect Transmission Fluid Quality and Level | Check the transmission fluid level and quality. Low fluid levels or degraded transmission fluid can lead to inadequate cooling and lubrication, affecting pump performance. Ensure the fluid is at the correct level and replace it if it appears dirty or burnt. | Transmission Fluid Dipstick, Transmission Fluid Replacement Tools |
| Replace Faulty Components as Needed | Replace any components identified as faulty during diagnostics, including the auxiliary transmission fluid pump, wiring, relays, or connectors. Ensure all replacement parts meet manufacturer specifications to maintain optimal transmission performance. | Replacement Pump, Wiring Repair Kit, Relays |
| Clear the Code and Test Drive | After completing the necessary repairs, use an OBD-II scanner to clear the P2797 code. Conduct a test drive to ensure the auxiliary transmission fluid pump is operating as expected and that transmission fluid flow and pressure are adequate during various driving conditions. | OBD-II Scanner |
| Recheck for Codes | Perform a final scan to ensure the P2797 code has not returned. If the code persists, further diagnostics may be required to address any ongoing issues affecting the performance of the auxiliary transmission fluid pump. | OBD-II Scanner |
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