EVAP Leak Detection Pump Sense Circuit Intermittent/Erratic
The P2407 code indicates that the Engine Control Module (ECM) has detected an intermittent or erratic signal from the evaporative emission (EVAP) leak detection pump sense circuit. This pump is part of the EVAP system's leak detection module, which pressurizes the system to check for leaks. An intermittent signal suggests a loose connection, damaged wiring, or a failing pump. This can cause the EVAP system to malfunction, potentially leading to a check engine light and failed emissions tests.
1. Most Common Causes
- Loose, corroded, or damaged electrical connections in the LDP pump sensor circuit
- Intermittent short to ground or voltage in the wiring
- Faulty LDP pump detection sensor
- Intermittent mechanical failure of the leak detection pump (LDP)
- Moisture or corrosion in EVAP harness connectors
- Intermittent ECM/PCM failure (less common)
2. Symptoms You Will Notice
- Check Engine Light illuminated
- Failed emissions test
- Possible fuel odor
- No noticeable drivability issues
3. Step-by-Step Diagnosis
Step 1: Use a scan tool to confirm P2407 and check for other EVAP codes.
Step 2: Visually inspect the EVAP leak detection pump and its wiring harness for damage, corrosion, or loose connections.
Step 3: Test the pump's electrical circuit with a multimeter for continuity and proper voltage (typically 12V).
Step 4: Perform a bidirectional test of the pump using a scan tool to verify operation.
Step 5: If wiring and pump check out, test the ECM's ability to read the pump signal; replace pump if faulty.
4. Frequently Asked Questions
Is it safe to drive with this code?▼
Yes, it is generally safe to drive as it does not affect engine performance or safety. However, it will cause the check engine light to stay on and may lead to a failed emissions test.
How much does it cost to fix?▼
The cost typically ranges from $50 to $150 for diagnosis and repair, depending on the cause. Replacing the leak detection pump can cost $100-$200 for parts and labor.
5. Commonly Affected Makes
This is a generic OBD2 code, potentially applicable to any manufacturer using this diagnostic standard.