93 300SE O2 sensor heater problem
 

I have a code 22 on pin 4 on my 93 300SE that states O2 sensor heater, open or short circuit. Barring a loose connection where the wire locks on to the harness, I assume I simply need to replace the O2 sensor? Is there a separate connection for the heater portion between the O2 sensor and the ECM?

Follow-up: The O2 sensor and section of pipe with the bung has been removed. I will take it to my exhaust guy and have the bung reinstalled and install a new O2 sensor.