Evaporative Emission System Leak Detection Pump Control Circuit Low
The control circuit for the leak detection pump is reading low voltage.
Heads up: this code wasn't in our hand-written library yet, so DiagCoach AI built this page on the fly. Double-check critical specs against service info before condemning parts.
What it means (plain English)
Inside the vehicle’s computer, there's a part called the leak detection pump that helps check for leaks in the fuel system. When the computer tries to turn on this pump, it's not getting the right voltage, making it think there's an issue.
What the computer is actually seeing
The engine control module (ECM) expects to see a voltage around 12-14 volts when the leak detection pump is activated. A reading below 5 volts or no voltage indicates a problem.
What a healthy reading looks like
Voltage at the leak detection pump connector should be 12-14 volts when activated; continuity between connectors should be less than 5 ohms.
Guided diagnostic — the DiagCoach way
Don't just throw parts at it. Walk through these in order — each step tells you whether to keep going or stop and fix what you found.
- 11. Verify that the battery voltage is within 12-14 volts and check for blown fuses related to the emissions system.
- 22. Inspect wiring and connectors at the leak detection pump for visible damage, corrosion, or loose connections. Repair as necessary.
- 33. If wiring is good, connect a multimeter to the leak detection pump connector and check for voltage while trying to activate the pump (via scan tool or manually). You should see 12-14 volts when activated.
- 44. If no voltage is present, trace the circuit back to the ECM and check for continuity. If there's no continuity, repair the circuit as required.
- 55. If voltage is present but the pump doesn't activate, replace the leak detection pump.
Common causes
- Damaged wiring or connectors to the leak detection pump
- Faulty leak detection pump
- Failed engine control module (ECM)
- Blown fuse
- Corroded connections at the pump or ECM
Typical repair cost
$$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
It's generally safe, but you might experience emissions issues, and your vehicle could fail an emissions test.
Will this problem come back after I fix it?
If the wiring and connectors are repaired as needed, and the pump is replaced if faulty, it should not return.
Why is this code paired with other codes?
Codes related to emissions systems often show together because they can all be affected by the same issues, like vacuum leaks or electrical failures.
Working a real vehicle right now?
Let DiagCoach walk you through it live with your specific symptoms, vehicle, and what you've already checked.
Start guided diagnostic →