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O2 Sensor Heater QuickFix

The Oxygen sensor heater maintains a sensor temperature of about 600 degrees Fahrenheit or 315.5 degrees Celcius. This is the normal operating temperature for the O2 sensor. Here are the facts about the O2 sensor.

1) The O2 sensor won't work below 600 drees Fahrenheit.
2) The O2 sensor is not the same as an Air Fuel Ratio Sensor. The O2 sensor is an older technology.
3) The O2 heater maintains a specific temperature at the O2 sensor.
4) Zirconius and Titania are the two types of O2 material. Zirconium being the most common one.
5) The O2 heater current is about 2 Amps, and have a resistance of about 6 Ohms.
6) If the ECM detects an O2 heater issue, it will shut off the heater circuit, making it seem like the ECM is bad. So, in this case erase the code.
7) Some cars the O2 sensor heater is pulse width modulated to control temperature.
8) An O2 heater circuit LOW code means circuit is below 0.3 Amps. A circuit HIGH means circuit current above 2 Amps.
9) There are three ways to test the O2 sensor heater, testing the ECM response, checking resistance, and checking current flow.
10) To check ECM response, use a series connected 10 Ohm resistor and testlight. The ECM needs to see about 10 Ohms resistance at the Heater circuit. The light should either stay On steady or flicker.
11) To check resistance, connect an Ohm meter in series with the O2 heater. However, this test is not conclussive, unless there is a complete open circuit, since the O2 heater tends to fail after it's hot.
12) To do a current flow test, connect an Amp meter in series with the O2 heater. If O2 heater stays On, look for about 2 Amps. If O2 heater flickers, look for between 0.5 or half an Amp to 2 Amps.

Remember that the ECM will shut Off the O2 heater circuit in the event of a malfunction, so you may need to erase codes. That's it for the O2 sensor heater QuickFix.