1. INPUT SENSORS OXYGEN SENSORS

2. 02 SENSOR DESIGN • THREADED INTO EXHAUST SYSTEM • ELEMENT INSIDE STEEL SHELL • ELEMENT MADE FROM ZIRCONIA • COVER OVER TOP PORTION AND ALLOWS OXYGEN TO OUTER PORTION OF ELEMENT CLASS PAGE 299, FIG 9-26

3. DESIGN • ONE WIRE • TWO WIRE • THREE WIRE • FOUR WIRE • SOME HAVE INTERNAL HEATERS

4. OPERATION • PRODUCES IT’S OWN VOLTAGE • O2 ON BOTH SIDES OF ELEMENT, PRODUCES A LOW VOLTAGE • DIFFERENT AMOUNTS OF OXYGEN ON BOTH SIDE OF ELEMENT, PRODUCES A HIGH VOLTAGE • VOLTAGE CHANGES OCCUR IN MILLISECONDS • CROSS COUNTS

5. CAUTIONS • IF LEAD COATS THE ELEMENT, GENERALLY WILL DESTROY SENSOR • IF ANTI-FREEZE OR RTV SILICONE IS USED, WILL RUIN 02 SENSOR • MUST USE A DIGITAL METER TO TEST • TIGHTENING - USE ANTI-SEIZE

6. TYPE OF 02 SENSORS • ZIRCONIA - PRODUCES IT’S OWN VOLTAGE • TITANIA - MODIFIES A BIAS VOLTAGE SENT TO IT FROM THE POWERTRAIN CONTROL MODULE • (USUALLY ABOUT .45 VOLTS)

7. 299C & 300C ZIRCONIA 02 SENSOR ZIRCONIA TYPE SENSOR GENERATES VOLTAGE

8. C301 TITANIA 02 SENSOR TITANIA SENSOR MODIFIES VOLTAGE

9. TESTING 02 SENSORS • 02 SENSOR MUST BE AT NORMAL OPERATING TEMP. (600 DEGREES) • DEDICATED SENSOR GROUND • AVOID PIERCING INSULATION (IF MUST, THAN RESEAL HOLE) • DON’T USE ANALOG METER • USE DVOM LAB PAGE 415

10. TESTING • SCANNER • USE ENGINE ANALYZER LAB SCOPE • USE PORTABLE LAB SCOPE • PROPANE TORCH • USE YOUR BODY TO TRICK PCM • HEATER DIAGNOSIS