Cruise Control Servo Control Circuit Low
The cruise control servo motor isn't receiving enough electrical current to function properly, similar to a weak battery struggling to power a device. This prevents the cruise control system from maintaining your set speed.
The ECM monitors the voltage and current supplied to the cruise control servo motor through its control circuit. It compares the measured signal against expected operating ranges and detects when the circuit voltage drops below the minimum threshold required for proper servo operation.
| Parameter | Normal Range | Fault Condition |
|---|---|---|
| Servo Control Circuit Voltage | 11-14 volts | Below 8 volts or open circuit |
| Servo Motor Current Draw | 0.5-2.5 amps during operation | Below 0.2 amps or no draw detected |
Code P0595 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, P0595 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.