Evaporative Emission System Leak Detection Pump Sense Circuit Open
The P2403 code means the vehicle's onboard diagnostic system has detected: Evaporative Emission System Leak Detection Pump Sense Circuit Open. This is a low severity code.
- Keep driving?
- Yes, but fix soon
- DIY difficulty
- moderate
- Estimated cost
- $100 - $450 (parts and labor)
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Common Symptoms
- Check Engine Light illuminated
- Failed emissions test
- No drivability symptoms
- EVAP readiness monitor incomplete
- Diagnostic trouble codes related to EVAP leak testing
Probable Causes (Ranked by Likelihood)
- Failed pressure sense circuit in leak detection pump Very High
- Broken sense wire from pump to ECM High
- Corroded connector at pump sense circuit Moderate
- ECM sense input circuit fault Low
Step-by-Step Diagnostic Procedure
-
Check the leak detection pump connector for all pins making contact
-
Measure voltage on the sense circuit wire with key on
-
Inspect the sense wire from the pump to the ECM for breaks
-
Check connector corrosion at the pump and ECM ends
-
Test the pump pressure sensor output with a scan tool
Frequently Asked Questions
Can I drive with code P2403?
Yes, safe to drive. This code only affects the EVAP leak testing capability and has no impact on engine operation.
What causes P2403?
Usually a failed pressure sensor inside the leak detection pump or a broken sense wire. The pump assembly typically needs replacement.
Is P2403 expensive to fix?
Typically $100 to $450. The leak detection pump assembly is the most common repair. Check wiring and connectors first.
Sources
This page is built from documented references. Verify against your own service info before repair work.
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