Pressure Control Solenoid "B" Intermittent Short
The transmission's pressure control solenoid B is experiencing an intermittent electrical short circuit, like a light switch that occasionally touches the metal frame. This causes the transmission to lose precise pressure control, affecting shift quality and performance.
The ECU monitors solenoid B's electrical resistance and current draw during operation. It detects brief short-to-ground or short-to-power conditions that occur intermittently, causing voltage spikes or drops outside normal operating parameters.
| Parameter | Normal Range | Fault Condition |
|---|---|---|
| Solenoid Current Draw | 0.5-1.5 amps during activation | Sudden spikes or drops indicating short circuit |
| Solenoid Resistance | 8-15 ohms (coil impedance) | Erratic readings or near-zero ohms intermittently |
Code P1907 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, P1907 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.