P2405: EVAP System Leak Detection Pump Sense Circuit Low

P2405 is set when the feedback signal of the leak detection pump stays below its permitted window, typically from a short to ground on the sense line or a fault inside the pump. No public source states a voltage threshold for this code. It appears in Maserati's sheet MAS002203 (2020) for DMTL-equipped M156/M157/M161 petrol models from MY17, which notes that most DMTL checks run with the key off; Land Rover's SSM69118 and SSM71298 treat a confirmed P2405 as a defect within the DMTL pump, and the 2021 bulletin JLRTB02068NAS1 blames dirt entering through the pump's dust filter and replaces pump and filter cover. P2406 is the high-side counterpart, P2403 a missing signal. The car drives normally, but the EVAP test result is lost.

Low severity. Can I keep driving?Yes, you can normally keep driving. If there is a strong smell of gasoline, find the leak before continuing and do not smoke nearby.

Symptoms

Check engine light, possibly set while the car is parked
No effect on drivability

Most likely causes

Internal DMTL pump fault, often after dirt ingress through the dust filter
Sense wire shorted to ground
Corroded connector at the pump mounted near the rear wheel arch

What to check, in order

Start with the simplest. You can tick off each step.

Start with the fuel cap: tighten it fully and check its seal
With the connector unplugged, check whether the signal wire is making contact with ground.
Inspect the hoses and connections around the tank and the charcoal canister
Use the scanner to test the purge and vent solenoid valves
Run a smoke test to find small leaks

Good to know

Repair difficulty: medium
It affects emissions.

What each character of P2405 means

P: Powertrain: engine and transmission
2: Generic code: same on every make
4: Emissions
05: Specific fault in that system

Frequently asked questions

Can I keep driving with code P2405?

Yes, you can normally keep driving. If there is a strong smell of gasoline, find the leak before continuing and do not smoke nearby.

What causes code P2405?

The most common causes are: internal DMTL pump fault, often after dirt ingress through the dust filter; sense wire shorted to ground; corroded connector at the pump mounted near the rear wheel arch.

Related codes

Sources

Values and procedures vary by manufacturer. If it affects brakes, steering, fuel or high voltage, see a professional. Updated: 2026-11-04. How we build these pages.