Multi-code OBD2 diagnosis
Enter all the codes your scanner showed, not just the first one. We give you the overall severity, whether you can keep driving, the order in which to check them and how they relate to each other.
Summary
- Overall severity
- Medium
- Can I keep driving?
- Yes, but with caution
- Estimated cost
- $40 to $350
- Codes analyzed
- 1 of 1
The order below is the recommended one: first the codes that can cause the others. After each repair, clear the codes and check which ones come back.
Order of inspection
P0509 Idle Air Control System Circuit High Medium
The P0509 code means the computer sees high voltage in the control circuit of the idle air control valve, either an open circuit or a short to voltage. It can cause a rough or high idle, or an engine that stalls. Start with the connector and the wiring before you replace the valve.