The P0991: Transmission Fluid Pressure Sensor/Switch ‘E’ Circuit Intermittent refers to an intermittent problem with the transmission fluid pressure sensor/switch ‘E’ circuit. This can cause irregular transmission fluid pressure readings, leading to unpredictable transmission performance.
P0991 – Quick Overview
| Code | Information |
|---|---|
| Meaning | P0991: Transmission Fluid Pressure Sensor/Switch ‘E’ Circuit Intermittent |
| Is it serious? | Yes, intermittent sensor issues can cause inconsistent transmission operation and affect vehicle performance. |
| Possible causes | – Intermittent issues with the transmission fluid pressure sensor/switch ‘E’ circuit – Wiring or connector issues – Faulty transmission fluid pressure sensor/switch ‘E’ |
| How to diagnose? | – Test for intermittent faults in the circuit – Inspect wiring and connectors – Replace faulty components if needed |
P0991 Meaning
The P0991: Transmission Fluid Pressure Sensor/Switch ‘E’ Circuit Intermittent code indicates that the transmission fluid pressure sensor/switch ‘E’ is experiencing intermittent issues, possibly caused by faulty wiring or a failing sensor. These irregularities can cause the sensor to give inaccurate pressure readings, leading to erratic shifting and transmission performance problems.
Step-by-step diagnostic guide
| Action | Description | Tools Needed |
|---|---|---|
| Check for Other Codes | Use an OBD-II scanner to check for any additional fault codes that may help provide more insight into the intermittent issue. | OBD-II Scanner |
| Test for Intermittent Faults | Use a diagnostic tool to test the transmission fluid pressure sensor/switch ‘E’ circuit for intermittent faults. Monitor the sensor’s output over time. | Multimeter, Diagnostic Tool |
| Inspect Wiring and Connectors | Inspect the wiring and connectors for signs of damage, corrosion, or loose connections that could cause intermittent issues in the sensor circuit. | Flashlight, Multimeter |
| Test the Sensor | Test the transmission fluid pressure sensor/switch ‘E’ for consistent performance. Replace the sensor if it is found to be faulty or providing inconsistent readings. | Diagnostic Tool, Replacement Sensor |
| Clear the Code and Test Drive | After making repairs, clear the code using an OBD-II scanner and take the vehicle for a test drive to confirm the issue is resolved. | OBD-II Scanner, Vehicle Owner’s Manual |
| Recheck for Codes | Re-scan the system to ensure the P0991 code does not return after the test drive. | 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