down stream o2

[hookit]

customer has a 2003 nissan 350z. Has repeated fault for bank one sensor 2s
heater failure. has replaced the sensor with aftermarket and oem. the question i have is the heater control. Is it a modulated ground...

[Crusty]

customer has a 2003 nissan 350z. Has repeated fault for bank one sensor 2s
heater failure. has replaced the sensor with aftermarket and oem. the question i have is the heater control. Is it a modulated ground...

Don't know the answer to your specific question but I understand what you're asking.
What is the code number as there could be slight variations of codes that all relate to the post-cat heater.
Sometimes the manufacturer doesn't come right out and say it but we might be able to figure that out depending on the code testing instructions.

Also see if you can figure out what the code set criteria is. That way the vehicle can be tested under the same conditions that the ECM wants to perform its' self test.

And BTW, welcome to the forums. There are some good guys here (and probably some gals too)

[hookit]

po037 is the fault. all wiring seams to be fine. has power and ground. takes about 6 to 7 miles for fault to return. the fault reads heater low crrrent. the vehicle belongs to the window installer here at the dealership and has even tried sending out the pcm for repair. I`ve never had good luck with nissan pcms being repaired. I believe the pcm control is a pulse ground. going to have him bring in the car and see whats on the control circuit.

[Crusty]

I just looked it up now that we have the details.
YES the ecm turns it on or off depending on circumstances....coolant....rpm.....under test mode with Consult scan tool.
Thete are also a couple of junctions or "joint connectors" in the circuit and the code chart directs you to TEST the circuitry under various conditions.
What dealer are you at and maybe you should get a hold of the code chart.
Costs less thsn guessing.