Contents Wiring diagrams Section: Testing & Diagnostics All sections

P0452 and P0453 Lexus GS III

Testing & Diagnostics 4 illustrations ~137 words

The ECM sensor pressure in the fuel tank using the vapor pressure sensor. The ECM supplies the sensor with a regulated 5 V reference voltage and the sensor returns a signal voltage between 0.5 V and 4.5 V according to the pressure level in the fuel tank.

If the output voltage of the vapor pressure sensor is out of the normal range, the ECM will determine that there is a malfunction in the sensor or sensor circuit.

When pressure indicated by the vapor pressure sensor deviates below -3.999 kPa (-30 mmHg, -1.18 in.Hg) or above 1.999 kPa (15 mmHg, 0.59 in.Hg), the ECM interprets this as a malfunction in the vapor pressure sensor. The ECM will turn on the MIL and a DTC will be set.

Scheme 330

Scheme 330: P0451

Scheme 331

Scheme 331: P0452 and P0453

Scheme 332

Scheme 332: P0451

Scheme 333

Scheme 333: P0452 and P0453