97 Thunderbird LX V8 P0155 and P0161

[lonewolf94]

Hi everyone, the check engine light recently came on my car and found codes P0155 and P0161, O2 heater circuit codes for both sensors on bank 2. I disconnected each sensor to test and measured around 25 ohms resistance on each sensor. I decided to replace the sensors anyway even though I thought it was somewhat odd for both sensors to go bad at the same time. After I replaced the sensors, the same two codes came back. So I went back at the connector, and I have 12 volts on the power wire but I do not have ground on the heater ground wire.

Does anyone have a wiring diagram for the O2 sensors for the 4.6 Thunderbird? Do these sensors receive ground from the ECM?

 

[dennis461]

Hi everyone, the check engine light recently came on my car and found codes P0155 and P0161, O2 heater circuit codes for both sensors on bank 2. I disconnected each sensor to test and measured around 25 ohms resistance on each sensor. I decided to replace the sensors anyway even though I thought it was somewhat odd for both sensors to go bad at the same time. After I replaced the sensors, the same two codes came back. So I went back at the connector, and I have 12 volts on the power wire but I do not have ground on the heater ground wire.

Does anyone have a wiring diagram for the O2 sensors for the 4.6 Thunderbird? Do these sensors receive ground from the ECM?

 

[dennis461]

Yes, PCM pin 93 controls ground for HO2S1, pin 94 HO2S2, pin 95 HO2S3, pin 96 HO2S4, pin 97 HO2S4. There is another connector C168 where all four wires pass through; under hood passenger side near firewall, 12 pins gray color..

 

[Mlnice]

Any update on issue? Did you get the codes to clear? O2 sensors fine?