Servo Motor Potentiometer Airintake Right Circuit Open
The right air intake servo motor's position sensor has lost its electrical connection, like a broken wire to a volume knob. Your engine can't properly adjust the intake air amount, causing performance issues.
The ECU monitors the potentiometer voltage signal from the right air intake servo motor to confirm proper position feedback. It expects a variable voltage between 0-5V that changes as the servo moves. An open circuit produces no signal or constant zero voltage, triggering the fault.
| Parameter | Normal Range | Fault Condition |
|---|---|---|
| Potentiometer voltage | 0.5V - 4.5V (variable with servo position) | Below 0.1V or no signal detected for >2 seconds |
| Circuit resistance | Below 100 ohms (complete circuit) | Above 10,000 ohms (open circuit) |
Code B1289 is a low-severity fault. Your vehicle is generally safe to drive to a workshop for diagnosis. However, do not ignore it indefinitely — low-severity codes often indicate developing problems that become expensive if neglected. Book a diagnostic appointment within 2–4 weeks. If you notice any additional symptoms (rough running, power loss, unusual smells), treat it as higher priority.
Once the fault is repaired, B1289 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.