Oil Pressure Control Solenoid Circuit Malfunction
The engine's oil pressure control solenoid isn't working properly, so the ECU can't regulate oil flow correctly. Think of it like a faulty water valve that won't open or close on command.
The ECM monitors voltage and current signals from the oil pressure control solenoid circuit during normal operation. It detects open circuits, short circuits, or abnormal resistance that indicates the solenoid cannot energize or de-energize properly.
| Parameter | Normal Range | Fault Condition |
|---|---|---|
| Solenoid Control Voltage | 12V when commanded, 0V when off | Out-of-range voltage or no response to ECM commands |
| Circuit Resistance | 4-8 ohms nominal | Open circuit (infinite ohms) or short (near 0 ohms) |
Code P1694 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, P1694 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.