Air Assisted Injector Control Circuit or Circuit High
Your engine's air-assisted fuel injector control circuit is receiving too much voltage, like a water pipe getting over-pressurized. The ECU can't properly regulate the injector's valve opening and closing.
The ECU monitors the voltage signal sent to the air-assisted injector control solenoid. It expects a specific voltage range during activation and de-activation cycles. When voltage remains above the normal threshold, the ECU detects a high voltage fault condition.
| Parameter | Normal Range | Fault Condition |
|---|---|---|
| Injector Control Signal Voltage | 0-14.5V (typical PWM signal) | Sustained voltage above expected range or short to power |
| Circuit Resistance | 4-10 ohms per injector coil | Below 2 ohms (short circuit) or open circuit |
Code P0067 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, P0067 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.