The PCM/ECM determines if a front HO2S heater fault has occurred and sets DTC P0030 if the front HO2S heater control driver inside the PCM/ECM 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 Driving Cycles |
Item | Detecting Condition | Possible Cause |
DTC Strategy |
•
Evaluate O2 sensor heater performance | 1. Related fuse blown or missing 2. Heater control circuit open or short 3. Power supply circuit open or short 4. Poor connection or damaged harness 5. Faulty HO2S |
Enable Conditions |
•
No relevant failure
•
11 ≤ Battery voltage ≤ 16V
•
Sensor operative readiness (Tip temp. > 640°C(1,184℉) or 18sec. heating time after Dew-point detection)
•
Heater PWM > 1.56% | |
Threshold Value |
•
Front HO2S tip temp. : < 755°C(1,391℉) or > 900°C(1,652℉) | |
Diagnostic Time |
•
Temp. < 640°C(1,184℉) : 1sec.
•
640°C(1,184℉) < Temp. < 755°C(1,391℉) : 10sec.
•
900°C(1,652℉) < Temp. : 10sec. | |
Mil On Condition |
•
2 Driving Cycles |
