1. INPUT SENSORS OXYGEN SENSORS

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

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

4. OPERATION u 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 u VOLTAGE CHANGES OCCUR IN MILLISECONDS u CROSS COUNTS

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

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

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

8. TITANIA 02 SENSOR TITANIA SENSOR MODIFIES VOLTAGE C301

9. TESTING 02 SENSORS u 02 SENSOR MUST BE AT NORMAL OPERATING TEMP. (600 DEGREES) u DEDICATED SENSOR GROUND u AVOID PIERCING INSULATION (IF MUST, THAN RESEAL HOLE) u 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 u HEATER DIAGNOSIS