O2 Sensor Troubleshooting Help…..

I don't believe the 2 02 sensors are the same. They generally have different part numbers but the code that you have is dealing with the heater part of the O2 sensor so I'm not sure whether it's able to detect whether the O2 sensor is in heating which I don't think is the case It sees some trouble maybe in the line voltage that's supposed to make the heater heat could be as simple as a fuse blown

 

You want the downstream sensor. DENSO 2344623. Go to RockAuto.com where they have 'em for about $50
Don't waste your time with anything else.

 

is that bank 1 sensor 1 which is upstream sensor?

 

If I had the Gen 2 manual open right now I'd get the complete answer from the code's detection condition, but anyway, the fortune cookie already quoted said open circuit for the heater, so that's probably what the code detects.

 

I don't think I'd trust that scan tool as P2237 does not appear to be a valid code for a Gen 2.

There are no Gen 2 DTCs that reference 'positive current control open circuit' either.

As for bank 1 or bank 2, I'd want a valid code first just so I'm not chasing my tail.

However, P2238 and P2239 are valid codes:

• P2238 - Oxygen (A/F) Sensor Pumping Current Circuit Low (Bank 1 Sensor 1)
• P2239 - Oxygen (A/F) Sensor Pumping Current Circuit High (Bank 1 Sensor 1

I'd be inclined to try for a second opinion using a different scan tool.

 

I don't know but you have a little fuse puller in your fuse box and I would just lift them up and see which one is burnt or use my fluke and check em . Test light whatever .I'd be finished time I write this. Because in my vehicle there are never any fuses burnt ever for any reason and if there are we're going to find them 60 seconds there's only two places for them. But I don't know which one controls the heater circuit for the O2 sensor or sensors. Another way might be to turn the car on and measure the wires that the plug of the O2 sensor does the wire that runs the heat whether that's black and white or the blue or whatever I don't know can't remember I try never to touch the O2 senses except every 200,000 mi and that means replacing

 

Anyone that gets a cat stolen from a Gen 2 loses the downstream O2 sensor. Nobody I've ever seen in this situation loses or replaces the upstream sensor, which is mounted in the exhaust manifold and is a bit of a PITA. Anyone I've seen that has replaced the downstream sensor with a cheap chinese $15 sensor from ebay typically gets what they pay for. I've installed quite a handful of aftermarket cats on Gen 2s. That DENSO has been bulletproof.

 

Yep if the cat's taking they're certainly not unscrewing the sensor so be ready to buy a new one I've only had good luck with the denso and the Bosch that come with the plug and splice kits never had a problem with either.