Evaporative Emission System Leak Detection Pump Control Circuit Low
The control circuit for the evaporative emission leak detection pump has 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)
Your car's computer is getting a low voltage reading from the pump that checks for leaks in the fuel system, indicating it might not be working properly.
What the computer is actually seeing
The vehicle's control module is monitoring the voltage from the leak detection pump circuit, expecting at least 5V under normal operation but seeing less than 2V.
What a healthy reading looks like
The voltage at the leak detection pump connector should be between 5V to 12V when the system is active.
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. Check the wiring and connectors for physical damage, corrosion, or loose connections.
- 22. Measure the voltage at the leak detection pump connector while the pump is activated; it should be between 5V and 12V. If less than 5V, continue to step 3; if proper voltage, replace the pump.
- 33. Inspect the circuit for shorts to ground or opens between the pump and the ECM, using continuity testing.
- 44. If wiring is good, swap the leak detection pump with a known good unit (if available) to confirm operation.
Common causes
- Faulty leak detection pump
- Damaged wiring or connectors in the circuit
- Short to ground in the pump circuit
- Faulty engine control module (ECM)
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
Yes, but fix it soon to avoid emissions problems and potential failure of the vehicle's inspection.
Will the code come back after I reset it?
If the problem isn't fixed, yes, the code will likely return after a drive cycle.
Does this code relate to the fuel system?
Yes, it indicates issues related to fuel vapor and emissions control.
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