The PCM determines if a front HO2S heater fault has occurred and sets DTC P0030 if the front HO2S heater control driver inside the PCM fails, if HO2S is not operational (after an elapse of predetermined time) since engine start, or when the front HO2S tip temperature is out of normal working range.
Item | Detecting Condition | Possible Cause |
DTC Strategy |
•
Evaluate O2 sensor Element Temperature via measuring Element Resistance | 1. Related fuse blown or missing 2. Heater control circuit open or short 3. Power supply circuit open or short 4. Contact resistance in connectors 5. Faulty HO2S |
Enable Conditions |
•
O2 sensor pre-heating phase finished (dew point passed)
•
No relevant failure
•
Coolant temperature drop since the last engine stop > 25℃(77℉)
•
10V< Battery voltage <16V
•
3.5%< O2 sensor heater control duty < 96.5%
•
O2 sensor operative ready (to ensure no open circuit failure present) | |
Threshold Value |
•
HO2S internal resistance > 2500Ω~9500Ω | |
Diagnostic Time |
•
90 sec. | |
Mil On Condition |
•
2 Drive Cycles |
