Powertrain, generic (extended)

P24BD EVAP System Leak Detection Pump Switching Valve Control Circuit/Open

Check engine lightOn

EmissionsRelevant

Drive cycleNot required

Limp modeNo

P24BD points to the drive circuit of the switching valve inside the leak check module. This small solenoid moves the canister vent path between open air and the reference orifice, so the module can first measure a known leak and then test the real system. The code stands for an open or generally faulty control circuit. No manufacturer documents P24BD publicly; Mitsubishi's 2023 Outlander PHEV splits the same valve into P24BE and P24BF, where the valve is fed from a relay and switched to ground by the engine computer. CARB requires output components like this to be checked for circuit faults. Without a working valve the leak test cannot run; in Mitsubishi's design purge is blocked and the fuel door stays locked.

Likely causes

Switching valve coil open inside the leak check module

Open control or supply wire, blown fuse or relay fault

Corroded connector at the module

Output driver in the engine control module faulty

Symptoms

Malfunction indicator lamp on
EVAP leak test does not run
On some designs fuel door locked or purge disabled

Repair estimate

DifficultyMediumDIY possible

Parts and labour€60–500

Time0.5–2 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

evap leak detection pump switching valve

Related codes

P24BE P24BF P24C0 P24C1 P2418

References: law.cornell.edu, mitsubishitechinfo.com, mitsubishitechinfo.com.