DTC Advanced Diagnostics: P24C0 (3.0L Engine)
DTC P24C0: Evaporative Emission (EVAP) Leak Check Module Canister Change Over Valve Close Malfunction
General Description
When the canister change over valve is working normally, the value of the evaporative emission (EVAP) leak check module pressure sensor does not become vacuum pressure during the purge since the purge is always flowing except during the EVAP leak check and has a passage for relieving pressure when refueling. If the purge is done while the canister change over valve stuck closed or the atmosphere side of passage, pipe, dust filter, or drain connected to the canister change over valve is clogged, the buckling of fuel tank might occur due to over-vacuumed pressure. If the relative pressure calculated from the EVAP leak check module pressure sensor is a specified value during the purge, the powertrain control module (PCM) detects a malfunction and stores a DTC.
Monitor Execution, Sequence, Duration, DTC Type
| Execution | Once per driving cycle |
| Sequence | None |
| Duration | 1.0 second or more |
| DTC Type | Two drive cycles, MIL on |
Enable Conditions
| Condition | Minimum | Maximum |
|---|---|---|
| Engine coolant temperature [ECT Sensor 1]* | 140 deg.F (60 deg.C) | - |
*: Condition to start purge[ ]: HDS Parameter
| Condition | Minimum | Maximum |
|---|---|---|
| 12 volt battery voltage [Battery] | 10.5 V | - |
| Fuel feedback | Closed-loop | |
*: Condition to start purge[ ]: HDS Parameter
Malfunction Threshold
The EVAP leak check module pressure sensor is -2.69 kPa (-20.2 mmHg, -0.795 inHg) or less for at least 1.0 second during the purge.
Possible Cause
- Canister change over valve stuck closed
- Dust filter clogged
Confirmation Procedure
Operating Condition
- Start the engine, and let it idle until the radiator fan comes on.
- When the diagnosis does not finish at idle, drive at 30 - 75 mph (48 - 120 km/h) at EVAP canister purge valve duty [EVAP PC Duty] 20 % or more.
- Drive the vehicle in this manner only if the traffic regulations and ambient conditions allow.
Diagnosis Details
Conditions for setting the DTC
When a malfunction is detected during the first drive cycle, a Pending DTC is stored in the PCM memory. If the malfunction returns in the next (second) drive cycle, the MIL comes on and a Confirmed DTC, the freeze data, and the on-board snapshot are stored.
Conditions for clearing the DTC
The MIL is cleared if the malfunction does not return in three consecutive trips in which the diagnostic runs. The MIL, the Pending DTC, the Confirmed DTC, the freeze data, and the on-board snapshot can be cleared with the scan tool clear command.