So I've been battling a P0141 code (rear O2 sensor not heating up in time)

I've tested the sensor off the truck with 12 volts, and it heats up in about 2 mins.

Ive tested the resistance of the circuit and have gotten some weird readings.

The FSM says to test the sensors with the key on (engine not running), which I've been doing.

However, what I want to know in order to help focus my troubleshooting, is to know if the senors heat up with just the key on ( I believe they are supposed to, but not 100% sure)

So, if you have a 1996-1997 V6 4runner (mines a 5 speed if that matters?), I will paypal you some $ for your beverage of choice, if you could take the rear O2 sensor out of the exhaust, keep the connector connected, and turn the key on (not running) and let me know if the sensor gets warm and if it does, how long it took. Cold engine, obviously.

This will greatly help me understand the system and correct operation.

Thanks!

I had this code. Look at the connector. Mine had oil wicking up inside it. Electrical cleaner fixed it. Otherwise there may be corrosion in the pins.

the connector on the computer that you can see facing towards the passenger compartment? Or the connector on the O2 sensor? I've cleaned the connections at the O2 sensor, and have used alligator clips to connect the harness side connector to the O2 sensor (just to test) and the sensor does not heat up.


I've taken the connectors apart multiple times for various troubleshooting purposes...everything 'looks' nice and clean. Connector seats firmly into the computer.

thanks