The ECM monitors the vapor pressure sensor in two ways. One method examines the fluctuation of the electrical signal while the engine is idling. If the pressure signal varies beyond the specified range more than 7 times, the ECM interprets this as a fault in the vapor pressure sensor. The ECM also verifies that the pressure signal changes within the specified range. If the output of the sensor does not vary for 5 minutes while the intake air amount has been changing, the ECM interprets this as a fault in the vapor pressure sensor. Either fault will set DTC P0451 and the ECM will turn on the MIL.
Contents
Wiring diagrams Section: Testing & Diagnostics- Sfi System - Diagnosis: Overview
- Sfi System - Diagnosis: Diagnosis
- Sfi System - Diagnosis: Wiring
- Sfi System - Diagnosis: Other
- DTC P0031: OXYGEN (A/F) SENSOR HEATER CONTROL CIRCUIT LOW (BANK 1 SENSOR 1), DTC P0032 OXYGEN (A/F) SENSOR HEATER CONTROL CIRCUIT HIGH (BANK 1 SENSOR 1), DTC P0051 OXYGEN (A/F) SENSOR HEATER CONTROL CIRCUIT LOW (BANK 2 SENSOR 1), DTC P0052 OXYGEN (A/F) SENSOR HEATER CONTROL CIRCUIT HIGH (BANK 2 SENSOR 1)
- DTC P0120: THROTTLE/PEDAL POSITION SENSOR/SWITCH "A" CIRCUIT, DTC P0122 THROTTLE/PEDAL POSITION SENSOR/SWITCH "A" CIRCUIT LOW INPUT, DTC P0123 THROTTLE/PEDAL POSITION SENSOR/SWITCH "A" CIRCUIT HIGH INPUT, DTC P0220 THROTTLE/PEDAL POSITION SENSOR/SWITCH "B" CIRCUIT, DTC P0222 THROTTLE/PEDAL POSITION SENSOR/SWITCH "B" CIRCUIT LOW INPUT, DTC P0223 THROTTLE/PEDAL POSITION SENSOR/SWITCH "B" CIRCUIT HIGH INPUT, DTC P2135 THROTTLE/PEDAL POSITION SENSOR/SWITCH "A"/"B" VOLTAGE CORRELATION
- DTC P0121: THROTTLE/PEDAL POSITION SENSOR/SWITCH "A" CIRCUIT RANGE/PERFORMANCE PROBLEM
- DTC P0128: COOLANT THERMOSTAT (COOLANT TEMPERATURE BELOW THERMOSTAT REGULATING TEMPERATURE)
- DTC P0351: IGNITION COIL "A" PRIMARY/SECONDARY CIRCUIT, DTC P0352 IGNITION COIL "B" PRIMARY/SECONDARY CIRCUIT, DTC P0353 IGNITION COIL "C" PRIMARY/SECONDARY CIRCUIT, DTC P0354 IGNITION COIL "D" PRIMARY/SECONDARY CIRCUIT, DTC P0355 IGNITION COIL "E" PRIMARY/SECONDARY CIRCUIT, DTC P0356 IGNITION COIL "F" PRIMARY/SECONDARY CIRCUIT
- P0441
- P0446
- P0442, P0456
- P0451
- P0452 and P0453
- DTC P2120: THROTTLE/PEDAL POSITION SENSOR/SWITCH "D" CIRCUIT, DTC P2122 THROTTLE/PEDAL POSITION SENSOR/SWITCH "D" CIRCUIT LOW INPUT, DTC P2123 THROTTLE/PEDAL POSITION SENSOR/SWITCH "D" CIRCUIT HIGH INPUT, DTC P2125 THROTTLE/PEDAL POSITION SENSOR/SWITCH "E" CIRCUIT, DTC P2127 THROTTLE/PEDAL POSITION SENSOR/SWITCH "E" CIRCUIT LOW INPUT, DTC P2128 THROTTLE/PEDAL POSITION SENSOR/SWITCH "E" CIRCUIT HIGH INPUT, DTC P2138 THROTTLE/PEDAL POSITION SENSOR/SWITCH "D"/"E" VOLTAGE CORRELATION
- DTC P2121: THROTTLE/PEDAL POSITION SENSOR/SWITCH "D" CIRCUIT RANGE/PERFORMANCE
- DTC P2195: OXYGEN (A/F) SENSOR SIGNAL STUCK LEAN (BANK 1 SENSOR 1), DTC P2196 OXYGEN (A/F) SENSOR SIGNAL STUCK RICH (BANK 1 SENSOR 1), DTC P2197 OXYGEN (A/F) SENSOR SIGNAL STUCK LEAN (BANK 2 SENSOR 1), DTC P2198 OXYGEN (A/F) SENSOR SIGNAL STUCK RICH (BANK 2 SENSOR 1)
- DTC P2237: OXYGEN SENSOR PUMPING CURRENT CIRCUIT/OPEN (FOR A/F SENSOR) (BANK 1 SENSOR 1), DTC P2238 OXYGEN SENSOR PUMPING CURRENT CIRCUIT LOW (FOR A/F SENSOR) (BANK 1 SENSOR 1), DTC P2239 OXYGEN SENSOR PUMPING CURRENT CIRCUIT HIGH (FOR A/F SENSOR) (BANK 1 SENSOR 1), DTC P2240 OXYGEN SENSOR PUMPING CURRENT CIRCUIT/OPEN (FOR A/F SENSOR) (BANK 2 SENSOR 1), DTC P2241 OXYGEN SENSOR PUMPING CURRENT CIRCUIT LOW (FOR A/F SENSOR) (BANK 2 SENSOR 1), DTC P2242 OXYGEN SENSOR PUMPING CURRENT CIRCUIT HIGH (FOR A/F SENSOR) (BANK 2 SENSOR 1), DTC P2251 OXYGEN SENSOR REFERENCE GROUND CIRCUIT/OPEN (FOR A/F SENSOR) (BANK 1 SENSOR 1), DTC P2252 OXYGEN SENSOR REFERENCE GROUND CIRCUIT LOW (FOR A/F SENSOR) (BANK 1 SENSOR 1), DTC P2253 OXYGEN SENSOR REFERENCE GROUND CIRCUIT HIGH (FOR A/F SENSOR) (BANK 1 SENSOR 1), DTC P2254 OXYGEN SENSOR REFERENCE GROUND CIRCUIT/OPEN (FOR A/F SENSOR) (BANK 2 SENSOR 1), DTC P2255 OXYGEN SENSOR REFERENCE GROUND CIRCUIT LOW (FOR A/F SENSOR) (BANK 2 SENSOR 1), DTC P2256 OXYGEN SENSOR REFERENCE GROUND CIRCUIT HIGH (FOR A/F SENSOR) (BANK 2 SENSOR 1)
- Abbreviations
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