Transmission Fluid Pressure Sensor/Switch E Circuit
The transmission's fluid pressure sensor (Sensor E) isn't sending the right signal to the engine computer, like a broken gauge that can't tell you if your tire pressure is correct. This prevents the transmission from adjusting properly and can cause shifting problems.
The ECM monitors voltage/resistance output from transmission fluid pressure sensor E to verify hydraulic pressure levels in real-time. The sensor should produce a varying signal proportional to fluid pressure, and the ECM compares this against expected pressure maps for current engine load and gear selection.
| Parameter | Normal Range | Fault Condition |
|---|---|---|
| Sensor Voltage Output | 0.5–4.5 volts (varies with pressure) | Below 0.1V or above 4.9V, or no signal |
| Fluid Pressure (logical) | 20–300+ psi depending on gear | Pressure reading implausible or missing |
Code P0987 is a moderate fault. You can generally drive to a workshop, but avoid long trips or high-load driving (motorway, uphill towing) until it is diagnosed. If the code keeps returning after clearing, or if you notice the symptoms listed above worsening, do not delay professional diagnosis. Many moderate codes have multiple possible root causes — a mechanic with live OBD data can identify the exact fault more efficiently than part-by-part trial and error.
Once the fault is repaired, P0987 can be cleared using any OBD-II scanner. Connect the scanner, navigate to "Clear Codes" or "Erase DTCs," and confirm. The check engine light turns off immediately.
The code will return if the root cause was not actually fixed. The ECM re-detects the fault within 1–3 drive cycles and sets the code again.