• NAXJA is having its 18th annual March Membership Drive!!!
    Everyone who joins or renews during March will be entered into a drawing!
    More Information - Join/Renew
  • Welcome to the new NAXJA Forum! If your password does not work, please use "Forgot your password?" link on the log-in page. Please feel free to reach out to [email protected] if we can provide any assistance.

o2 sensor help please

drknyt

NAXJA Forum User
Location
Cedar City, UT
i just replaced my o2 sensor post cat, and i guess i didnt tie the plug up enough, and now it rubbed against the driveline and wore through so i need someone one to look under their jeep and tell me which wires the 2 white ones the gray one and the black one hook to, the wires coming out of the female plug on the jeep side are different colors, can someone just check and tell me what goes where
 
We need a year model to help you out? I would guess its OBD2 so it is a 96+ but the wire colors may change at the body revamp in 97
 
Sounds like a standard 4-wire bosch o2 sensor. The black wire should be the signal wire, and the grey should be signal ground. The two white are for the heater. If you have a meter, you can probably figure out one of the heater wires by looking for +12volts. The other heater wire and the signal ground wire should have very low resistance to the body ground.

This might help.
http://home.earthlink.net/~jcgebhart/o2sens.html
http://www.taligentx.com/passat/inf...osch-Universal-Oxygen-Sensor-Installation.pdf

If it's a 99, checkout http://www.montanafab.com/documents/Instructions_o2_w_heat_word.pdf

Or if you post the year, I can probably look up the wire colors. Your profile says 94, but I didn't think that had the post cat sensor.
 
Last edited:
The 2000 FSM has the following:
Pin 1 => VT/OR FUSED AUTOMATIC SHUT DOWN RELAY OUTPUT (DG/WT for 2.5l)
Pin 2 => BK GROUND
Pin 3 => BR/YL SENSOR GROUND
Pin 4 => TN/WT OXYGEN SENSOR 1/2 SIGNAL

So:
Pins 1 and 2 go to the white wires for the heater on the sensor.
Pin 3 to the grey ground wire on the sensor
Pin 4 goes to the black sensor wire

Which agrees with the 1999 diagram in the montana fab link, except I think they listed the 2.5l color for the asd +12 feed.
 
Back
Top