LEMON Manuals: Even more car manuals for everyone
Home >> Lexus >> 2007 >> RX 400h AWD >> Repair and Diagnosis >> Engine Performance >> Engine Control System >> SFI System >> DTC P1420 Evaporative Emission Canister Small Leak; DTC P1421 Evaporative Emission Canister Gross Leak >> Monitor Description

Monitor Description

  1. P1420: EVAP (Evaporative Emission) very small leak

    In operation C, the vacuum pump creates negative pressure (vacuum) in the EVAP system and the EVAP system pressure is measured. If the stabilized system pressure is higher than the second 0.02 inch leak pressure standard, the ECM (included in the HV control ECU) determines that the EVAP system has a large leakage. The ECM illuminates the MIL and sets the DTC (2 trip detection logic).

  2. P1421: EVAP very gross leak

    In operation C, the vacuum pump creates negative pressure (vacuum) in the EVAP system and the EVAP system pressure is measured. If the stabilized system pressure is higher than (second 0.02 inch leak pressure standard x 0.2) (near atmospheric pressure), the ECM (included in the HV control ECU) determines that the EVAP system has a large leakage. The ECM illuminates the MIL and sets the DTC (2 trip detection logic).

Fig 1: EVAP Pressure Graph (EVAP Very Gross Leak)
G05200115Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002