P1513 IAC Circuit Open
The P1513 code indicates that the powertrain control module (PCM) has detected an open circuit in the idle air control (IAC) system. This prevents the PCM from properly regulating engine idle speed. This code is specific to Ford and its associated brands, where the IAC system uses an electronically controlled valve to adjust bypass air flow around the throttle plate.
01. Most Common Causes
- Faulty IAC valve with internal coil failure
- Open or cut wiring in the IAC control circuit
- Corroded, loose, or disconnected IAC connector
- Faulty IAC control relay (if applicable)
- Excessive resistance in the IAC control circuit
- Failed PCM internal driver for the IAC circuit
02. Symptoms You Will Notice
- Rough or unstable idle
- Engine stalling at idle or when decelerating
03. Step-by-Step Diagnosis
Scan for codes and verify P1513 is present.
Inspect IAC valve connector for corrosion, damage, or looseness.
Test IAC valve resistance with a multimeter (specs vary by model).
Check for battery voltage and ground at the IAC connector with key on.
Test continuity and resistance in the wiring between PCM and IAC valve.
If all else passes, suspect a faulty PCM.
1. Frequently Asked Questions
Is it safe to drive?▼
You can drive short distances, but the vehicle may idle poorly or stall, especially at stops. It's best to repair promptly to avoid drivability issues.
How much does it cost to fix?▼
Typical repair costs range from $100 to $400, depending on whether the IAC valve needs replacement and labor rates.