Advice:

I have a question about testing an O2 sensor from a 2005 Tacoma with a 2TR-FE engine. I am following the FSM on page EC-27 near the bottom. It says to test the resistance for sensor terminals 1 to 2 which I did and it was in specs. Then it says test pins 1 to 4 which should be 10K or higher. I tried 2 different meters and I can't get any reading on either one. I have the rangeset to 20K and still nothing shows up on the meter. Am I testing this right or am I missing something. Thanks

 

1/4 might be an open circuit (failed). Only going to get resistance between pins if it has continuity.

 

What is on the meter screen when you check between pins 1 to 4?

It may read anywhere from 10K Ohms up to infinity or open circuit (OL) which IAW the manual is a good reading between pins 1 and 4. It depends on the meter.

As long as it doesn't read less than 10K ohms you should be good.

 

That is what they are looking for on Pins 1 to 4 "A High Resistance Circuit" as it says 10K Ohms or Higher... That would include an Open circuit.

 

Pins 1-4 are for the heater circuit. Even with the circuit failed it shouldn’t affect your readings once the engine is warmed up. Are you using a DMM or something like a Simpson to check for resistance?