1997 Tacoma 4WD, 4 cylinder with 290,000 miles. Replaced catalytic converter. No front oxygen sensor. Showing a high temperature code. What does the high temperature code mean and how do I clear it?
Do you know the number of the trouble code that is telling you of the high temp problem?
You would need a scanner to get the correct code, if you don't have one you can go to your local Auto Zone Auto Parts store and they should do if for free.
The only way to properly erase the code is to clear them with a scan tool or code reader.
You can also remove the EFI fuse (15A) for 30 seconds or more, depending on ambient temperature (the lower the temperature, the longer the fuse must be left out) with the ignition switch off.
Cancellation can also be done by removing the negative (-) terminal cable of the battery, but in this case other memory systems (radio ETR, etc.) will also be canceled out.
After cancellation, road test the vehicle, if necessary, confirm that a "normal" code is now read on the Malfunction indicator lamp. If the same diagnostic trouble code appears, it indicates that the trouble area may not have been repaired thoroughly.
The code is P0125 insufficient temp closed loop.
The PO125 is usually related to an open or short in the heated oxygen sensor circuit or the heated oxygen sensor itself.
In most cases the oxygen sensor heater is probably bad and needs to be changed.