Oxygen heater sensor diagnostic routine

Details Oxygen heater sensor diagnostic routine Oxygen heater sensor diagnostic routine

1993-11-22

1995-02-28

Chilcot, Jr., Richard E.

Measuring and testing

Simulating operating condition

Marine

G01M 1500

Patent

active

053926439

ABSTRACT:
A diagnostic method is provided for sensing whether an oxygen sensor is still suitable for use in measuring the fuel-air mixture in the exhaust gases of an internal combustion engine. The method involves turning off a heater of an oxygen sensor when the engine is turned off and allowing the sensor to cool. While the sensor cools, the sensor resistance is measured by means of a large pull-up resistor and a small pull-up resistor, with the small resistor being switched into the circuit at regular intervals for a short period of time. The use of the small pull-up resistor not only increases the reliability of the measurements, but also aids in quickly determining when the sensor resistance has increased above a threshold value indicating the sensor is cool. When the sensor is sufficiently cool, the heater is turned on and the sensor is monitored for a decrease in resistance, indicating that the heater is functioning properly.

REFERENCES:
patent: 4121548 (1978-10-01), Hattori et al.
patent: 4167163 (1979-09-01), Moder et al.
patent: 4172432 (1979-10-01), Wessel et al.
patent: 4177787 (1979-12-01), Hattori et al.
patent: 4178793 (1979-12-01), Bremer et al.
patent: 4208993 (1980-06-01), Peter
patent: 4214308 (1980-07-01), Carp
patent: 4214563 (1980-07-01), Hosaka
patent: 4223549 (1980-09-01), Kitzinger
patent: 4252098 (1981-02-01), Tomczak et al.
patent: 4430191 (1984-02-01), Sone et al.
patent: 4450812 (1984-05-01), Otsuka et al.
patent: 4450815 (1984-05-01), Mouri
patent: 4492205 (1985-01-01), Jundt et al.
patent: 4570069 (1986-02-01), Gager
patent: 4663717 (1987-05-01), Kobayashi et al.
patent: 4671243 (1987-06-01), Deutsch
patent: 4724814 (1988-02-01), Mieno et al.
patent: 4742808 (1988-05-01), Blumel et al.
patent: 4759328 (1988-07-01), Blumel et al.
patent: 4819602 (1989-04-01), Mieno et al.
patent: 4844038 (1989-07-01), Yamato et al.
patent: 4868508 (1989-09-01), Ohishi
patent: 4938194 (1990-07-01), Kato et al.
patent: 4951632 (1990-08-01), Yakuwa et al.
patent: 4958611 (1990-09-01), Uchinami et al.
patent: 5020499 (1991-06-01), Kojima et al.
patent: 5054452 (1991-10-01), Denz
patent: 5091698 (1992-02-01), Grabs
patent: 5096565 (1992-03-01), Kaganov
patent: 5111792 (1992-05-01), Nagai

Affiliated with

Also associated with

Rating

Oxygen heater sensor diagnostic routine does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Oxygen heater sensor diagnostic routine, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Oxygen heater sensor diagnostic routine will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-840369