System Description
The diagnostic strategy for the evaporative emission (EVAP) system uses a vacuum pump to test for system leaks, after the engine is OFF. A unique fuel tank, EVAP canister, and EVAP vacuum leak pump work together to provide enhanced system diagnosis. The vacuum leak pump, the fuel tank pressure (FTP) sensor and the EVAP canister vent valve are all integral parts of one assembly. The assembly is attached directly to the EVAP canister, located near the fuel tank.
After the vehicle has sat with the engine OFF for at least 5 hours and the engine coolant temperature is less than 35°C (95°F), a comprehensive diagnostic is enabled. The complete diagnostic test can take up to 15 minutes to run, with leak detection comprising the largest portion of the test. For more detailed information on the EVAP system components and diagnostic strategy, refer to Evaporative Emission Control System Description .
DTC Descriptor
This diagnostic procedure supports the following DTC:
DTC P2420 Fuel Tank Pressure (FTP) Control Solenoid Control Circuit High Voltage
Conditions for Running the DTC
| • | DTCs P0110, P0112, P0113, P0115, P0117, P0118, P0450, P0451, P0452, P0453, P2610 are not set. |
| • | Five hours have elapsed after the engine was turned OFF. |
| • | Atmospheric pressure is between 70-110 kPa. |
| • | Battery voltage is more than 10.5 volts. |
| • | Engine coolant temperature (ECT) is between 4-35°C (40-95°F). |
| • | Intake air temperature (IAT) is between 4-35°C (40-95°F). |
| • | The ignition remains OFF for the duration of the test. |
| • | DTC P2420 runs once per drive cycle when the above conditions are met. |
Conditions for Setting the DTC
The powertrain control module (PCM) has determined the EVAP vent solenoid may be stuck OFF, OPEN, because vacuum pressure was not obtained.
Action Taken When the DTC Sets
| • | The PCM illuminates the malfunction indicator lamp (MIL) after 2 consecutive ignition cycles in which the diagnostic runs with the fault active. |
| • | The PCM records the operating conditions at the time the diagnostic fails. This information is stored in the Freeze Frame buffer. |
Conditions for Clearing the MIL/DTC
| • | The PCM turns OFF the MIL on the third consecutive trip cycle during which the diagnostic has been run and the fault condition is no longer present. |
| • | A DTC will clear after 40 consecutive warm-up cycles have occurred without a fault. |
| • | A DTC can be cleared by using the scan tool Clear Information function. |
Test Description
The numbers below refer to the step numbers on the diagnostic table.
Step | Action | Values | Yes | No |
|---|---|---|---|---|
Schematic Reference: Engine Controls Schematics Connector End View Reference: Powertrain Control Module Connector End Views or Engine Controls Connector End Views | ||||
1 | Did you perform the Diagnostic System Check - Vehicle? | -- | Go to Step 2 | |
2 |
Did the test lamp illuminate? | -- | Go to Step 3 | Go to Step 5 |
3 |
Did you find and correct the condition? | -- | Go to Step 11 | Go to Step 4 |
4 |
Did you find and correct the condition? | -- | Go to Step 11 | Go to Step 8 |
5 |
Is the voltage at the specified value? | B+ | Go to Step 7 | Go to Step 6 |
6 | Repair the open in the vent solenoid ignition positive voltage circuit. Refer to Wiring Repairs . Did you complete the repair? | -- | Go to Step 11 | -- |
7 |
Did you find and correct the condition? | -- | Go to Step 11 | Go to Step 9 |
8 | Replace the EVAP vacuum leak pump assembly. Refer to Evaporative Emission System Vacuum Leak Pump Replacement . Did you complete the replacement? | -- | Go to Step 11 | -- |
9 |
Did you find and correct the condition? | -- | Go to Step 12 | Go to Step 10 |
10 | Replace the PCM. Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement? | -- | Go to Step 12 | -- |
Is DTC P2420 set in Last Test Failed? | -- | Go to Step 2 | Go to Step 12 | |
12 |
Are there any DTCs that have not been diagnosed? | -- | System OK | |
