P0155-O2 Sensor 2/1 Heater Performance: Notes

Fig 1: O2 Sensor Heaters Circuit Schematic

Courtesy of CHRYSLER LLC

When Monitored : Engine Running and Heater duty cycle greater than 0%.
Set Condition : O2 Heater Temperature does not reach 575°C (959°F) within 90 seconds during monitoring conditions. Two Trip Fault.

Possible Causes
FUSED ENGINE CONTROL RELAY OUTPUT CIRCUIT OPEN
O2 SENSOR HEATER CONTROL CIRCUIT SHORT TO VOLTAGE
O2 SENSOR HEATER CONTROL CIRCUIT SHORT TO GROUND
O2 HEATER CONTROL CIRCUIT OPEN
O2 HEATER ELEMENT
POWERTRAIN CONTROL MODULE

For a complete Powertrain Control Module Circuit Diagram, refer to SCHEMATICS AND DIAGRAMS .