DTC P2420 Evaporative Emission System Switching Valve Control Circuit High
DTC SUMMARY
DESCRIPTION
The circuit description can be found in the EVAP (Evaporative Emission) System.
INSPECTION PROCEDURE
Refer to the EVAP System.
MONITOR DESCRIPTION
5 hours*1 after the ignition switch is turned off, the electric vacuum pump creates negative pressure (vacuum) in the EVAP (Evaporative Emission) system. The ECM monitors for leaks and actuator malfunctions based on the EVAP pressure.
HINT: *1: If the engine coolant temperature is not below 35C (95F) 5 hours after the ignition switch is turned off, the monitor check starts 2 hours later. If it is still not below 35C (95F) 7 hours after the ignition switch is turned off, the monitor check starts 2.5 hours later.
*2: If only a small amount of fuel is in the fuel tank, it takes longer for the EVAP pressure to stabilize.
The vent valve turns ON (closes) and the EVAP (Evaporative Emission) system pressure is then measured by the ECM, using the pressure sensor, to conduct an EVAP leak check. If the pressure does not increase when the vent valve is open, the ECM interprets this as the vent valve being stuck open. The ECM illuminates the MIL and sets the DTC.
MONITOR STRATEGY
TYPICAL ENABLING CONDITIONS
Key-off monitor sequence 1 to 8
1. Atmospheric pressure measurement
2. First reference pressure measurement
3. EVAP canister vent valve close stuck check
4. Vacuum introduction
5. EVAP canister purge valve close stuck check
6. Second reference pressure measurement
7. Leak check
8. Atmospheric pressure measurement
TYPICAL MALFUNCTION THRESHOLDS
MONITOR RESULT
Refer to CHECKING MONITOR STATUS
Brake Switch "B" Circuit High
DESCRIPTION
The purpose of this circuit is to prevent the engine from stalling while
driving in lock-up condition when
brakes are suddenly applied.
When the brake pedal is depressed, this switch sends a signals to the ECM. Then
the ECM cancels the
operation of the lock-up clutch while ...
Reassembly
1. INSTALL NO. 1 COOLER THERMISTOR
(a) Install the No. 1 cooler thermistor as shown in the
illustration.
NOTICE:
Be sure to insert the thermistor only once
because reinserting it will not allow it to be
firmly secured.
When reusing the evaporator, insert the
thermistor one row ne ...
Situations when it is necessary to contact dealers before towing
The following may indicate a problem with your transaxle. Contact
your Toyota dealer or commercial towing service before towing.
The engine is running but the vehicle does not move.
The vehicle makes an abnormal sound
Towing with a sling-type truck
Do not tow with a sling-type truck
to p ...