P0155 O2 Sensor Heater Circuit Fault on 1995 Dodge Windstar - After Tranny and Valve Job
I'm experiencing a recurring P0155 diagnostic trouble code on my 1995 Dodge Windstar. The code indicates an O2 sensor heater circuit malfunction for Bank 2 Sensor 1, though all oxygen sensors have been recently replaced. The data stream shows stable readings from three of the sensors, but Bank 1 Sensor 1 exhibits erratic values and consistently falls outside acceptable tolerance limits. I've swapped the O2 sensors between positions in Bank 2 with no improvement—the code persists and the MIL (Malfunction Indicator Lamp) activates on every engine restart. The vehicle recently underwent a valve job and transmission rebuild, which may have affected wiring or grounding related to the sensor circuits. At this point, I'm considering replacing the Powertrain Control Module (PCM), as it's possible the PCM has lost proper control over the heater circuit for Bank 1 Sensor 1—especially given that the issue began prior to the transmission work and was previously intermittent. Any insights or troubleshooting steps would be greatly appreciated.
P0155 = O2 Sensor Heater Circuit Malfunction (Bank 2 Sensor -1). Check the wiring and electrical connections for Bank 2 sensor heater circuits. These may have been damaged or pinched during the transmission rebuild or valve job. Ensure all connectors are secure and properly grounded. A thorough inspection of the harness routing is recommended. Good luck—please update with your findings.