P2406: EVAP System Leak Detection Pump Sense Circuit High

P2406 is the mirror image of P2405: the pump feedback reads above its allowed range, as with a short to a voltage source or a sense line that floats high. Thresholds are not published. Jaguar's JTB00436 for the XJ (X351) includes P2406 among DMTL faults caused by water or ice from tyre spray caught in the pump filter and has the canister and filler pipe renewed. Maserati's DMTL sheet MAS002203 and Land Rover's SSM69118/SSM71298 list it as well, and JLR's 2021 bulletin JLRTB02068NAS1 (Range Rover, Discovery, Range Rover Sport) replaces the pump with a new dust filter cover after contamination. It differs from P2404 in that the signal leaves its electrical range instead of merely being implausible. Driving is unaffected.

Symptoms

• Check engine light
• Fault often appears after wet or freezing weather

Most likely causes

• Water or ice from road spray in the pump filter (Jaguar XJ)
• Sense wire shorted to a voltage feed or open ground at the pump
• Pump damaged by contamination entering through the dust filter

What to check, in order

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

1. Start with the fuel cap: tighten it fully and check its seal
2. Check the sensor's ground and make sure the signal wire is not receiving voltage from another circuit.
3. Inspect the hoses and connections around the tank and the charcoal canister
4. Use the scanner to test the purge and vent solenoid valves
5. Run a smoke test to find small leaks

Good to know

• Repair difficulty: medium
• It affects emissions.

What each character of P2406 means

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

Frequently asked questions

Can I keep driving with code P2406?

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 P2406?

The most common causes are: water or ice from road spray in the pump filter (Jaguar XJ); sense wire shorted to a voltage feed or open ground at the pump; pump damaged by contamination entering through the dust filter.

Related codes

• P2403EVAP System Leak Detection Pump Sense Circuit/Open
• P2405EVAP System Leak Detection Pump Sense Circuit Low
• P2402EVAP System Leak Detection Pump Control Circuit High

Sources

• static.nhtsa.gov: SB 10074551 2280
• static.nhtsa.gov: MC 10176340 9999
• static.nhtsa.gov: MC 10191845 0001
• law.cornell.edu: 13 CCR 1968.2

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.