The P0879: Transmission Fluid Pressure Sensor/Switch ‘D’ Circuit Intermittent refers to an issue where the transmission fluid pressure sensor/switch ‘D’ experiences intermittent faults. This can affect the transmission’s ability to maintain proper fluid pressure, leading to performance issues and potential drivability problems.
P0879 – Quick Overview
| Code | Information |
|---|---|
| Meaning | P0879: Transmission Fluid Pressure Sensor/Switch ‘D’ Circuit Intermittent |
| Is it serious? | Yes, this can lead to erratic shifting or transmission failure over time. |
| Possible causes | – Intermittent issues with the transmission fluid pressure sensor/switch ‘D’ – Wiring or connector issues – Faulty transmission control module (TCM) |
| How to diagnose? | – Test for intermittent faults in the circuit – Inspect wiring and connectors – Replace faulty components if needed |
P0879 Meaning
The P0879 fault code indicates an intermittent issue with the transmission fluid pressure sensor or switch ‘D’. When this sensor or switch doesn’t work consistently, it can send faulty signals to the transmission control module (TCM), leading to improper transmission fluid pressure readings and potentially erratic shifting behavior.
Step-by-step diagnostic guide
| Action | Description | Tools Needed |
|---|---|---|
| Check for Other Codes | Use an OBD-II scanner to check if there are other related transmission codes. | OBD-II Scanner |
| Inspect Wiring and Connectors | Visually inspect the wiring and connectors for the sensor/switch for any damage, corrosion, or loose connections. | Flashlight, Multimeter |
| Test Sensor/Switch for Intermittent Faults | Use a multimeter to test the sensor/switch for intermittent faults, focusing on voltage stability and continuity. | Multimeter |
| Verify Transmission Control Module (TCM) | If the sensor/switch is functioning properly, test the TCM for faults. | Diagnostic Tool, TCM Pinout Chart |
| Replace Faulty Components | If any faulty components are identified (sensor, wiring, or TCM), replace them as necessary. | Replacement parts, Tools |
| Clear Code and Test Drive | After repairs, clear the code and perform a test drive to verify the issue is resolved. | OBD-II Scanner, Vehicle Owner’s Manual |
| Recheck for Codes | After the test drive, re-scan the vehicle to ensure the code does not reappear. | OBD-II Scanner |
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I test OBD-II scanners and make DIY Engine diagnostics guides to help you solve your car problems without having to depend on the mechanic. A lot of them will try to scam you or are just no help at all. About Juraj Lukacko