XJ-S Convertible (XJ27) L6-4.0L (1996)
HO2S Sensor Heater Short Circuit - Banks land 2 Sensor 1, P1186
HO2S Sensor Heater Short Circuit - Banks land 2 Sensor 2, P1192
NOTE: The heaters are connected to the ECM; hardware detection will provide indication of both heaters open circuit and one or both heaters
short circuit.
Possible causes:
-
ECM to heater wiring is short circuit to voltage source
-
Both heaters short circuit - sensor
-
ECM hardware monitor fault implying short circuit heaters
Sensor Heater Open Circuit
HO2S Sensor Heater Open Circuit - Inferred - Banks 1 and 2 Sensor 1, P1187
HO2S Sensor Heater Open Circuit - Inferred - Banks 1 and 2 Sensor 2, P1193
NOTE: The heaters are connected to the ECM in pairs; hardware detection will provide indication of both heaters open circuit and one or both
heaters short circuit.
Possible causes:
-
Heater harness high resistance or open circuit
-
Excessive ignition retard causing hot exhaust gases
-
Both heaters high resistance
-
Incorrect test timing - air flow meter problem
-
Incorrect heater calibration - ECM programming
-
ECM fault - heater control system
Sensor Heater - Resistance
HO2S Sensor Heater - Resistance - Banks 1 and 2 Sensor 1, P1188
HO2S Sensor Heater - Resistance - Banks 1 and 2 Sensor 2, P1194
The heater current and average output tests use the closed loop tip temperature control system to indicate faults. If the closed loop system is unable
to control tip temperature then faults will be detected.
Possible causes:
-
ECM to heater wiring is open circuit
-
ECM to heater wiring is part open circuit
-
ECM to heater wiring is short circuit to ground
-
Battery voltage low and battery voltage sensing
-
Both heaters are high resistance or open circuit - sensor
-
ECM heater current monitor reads low
-
Incorrect heater calibration
-
ECM current sense resistor
Sensor Heater Circuit Low Resistance
HO2S Sensor Heater Circuit Low Resistance - 1 - Banks 1 and 2 Sensor 1, P1189
HO2S Sensor Heater Circuit Low Resistance - 1 - Banks I and 2 Sensor 2, P1195
The heater current and average output tests use the closed loop tip temperature control system to indicate faults. If the closed loop system is unable
to control tip temperature then faults will be detected.
Possible causes:
-
HC2S out of exhaust
-
Heater harness short circuit
-
Low battery voltage
-
Incorrect test timing - air flow meter problem
-
HO2S heater low resistance
-
Incorrect heater calibration - ECM programming
Sensor Heater Circuit Low Resistance
HO2S Sensor Heater Circuit Low Resistance -2- Banks 1 and 2 Sensor 1, P1190
HO2S Sensor Heater Circuit Low Resistance -2- Banks 1 and 2 Sensor 2, P1196
The heater current and average output tests use the closed loop tip temperature control system to indicate faults. If the closed loop system is unable
to control tip temperature then faults will be detected.
Possible causes: