My Icarsoft I930 is reporting a P1647 fault Bank 2 Sensor 1 upstream on driver side ( O2 open circuit....does that mean a failed heater ?) which turns on the CK engine lamp.
My question is simple.
Is it OK to swap the Bank 1 upper sensor connector with the failed Bank 2 upper sensor to see if the problem moves to bank 1 thererby confirming that bank two sensor is bad ?
Should I disconnect the battery before doing the swap and disconnect again before returning connectors to their original positions ?
any replies greatly appreciated

 

forgot to add...Car is a 2003 X308 XJR

 

No!

You would at best make the car wrongly do fuelling.

 

Please explain "wrongly do fueling ? thanks for a reply

 

It needs working O2s or can't get fuel right.

Just replace the bad one!!

 

I think you're missing the point here.....that being to PROVE there is a bad sensor without removing the thing..... point being that if the bad bank 2 bad sensor connector is swapped with he good Bank 1 sensor connector then a new failure code would be reported showing a bank one failure.... Capice ?

 

yes you can swap them

 

O2 sensors for our cars are kind of expensive, so I understand why you're asking the question vs just swapping it out. But I suspect that swapping the connectors wouldn't give you the answer. The car "thinks" that the connector is reading bank 1, when it would in fact be reading bank 2. It would be telling the bank 2 mixture to change, but since it's reading bank 1 and bank 1 is not "responding" to the mixture commands, it might throw a code anyway. That said, I don't know if it would hurt anything to try it, as long as it was just a temporary check. I have never tried that. I have always assumed that the reader was not lying to me, and changed out the faulty sensor. My official recommendation is to change the o2 sensor.

Backing up a step, I assume you're certain that you don't have a vacuum leak anyplace? Vacuum leaks will confuse the sensors and cause the CEL to come on.

 

I agree: if you are going to swap the upper sensor (especially since the port side is real bitch to get at), just replace. But . . . maybe a can of a really good fuel system cleaner first, tighten all joints to preclude any leaks, clean the MAF and check all of its prongs, and clean the throttle bore and plate.

My limited experience, however, is that a P1647 is rarely set unless the sensor is shot.

 

Thanks to all for replies................of course the sensor in question is the PITA driver side upper. I think they hung this sensor on a string and then built a car around it. I can't even seem to find the connector. Anyone have a picture as to where this connector (EM023 in the manual) is located ? If I can find it and disconnect it I can then meter the heater element to see if it has gone open circuit. The manual also says to relocate ( looks like "remove" to me) the Expansion tank so you can get at things . The manual also says that sensor is actually removed from underneath the car after two bolts holding the front exhaust bracket are removed so that the front exhaust pipes can be moved ( removed?) to gain access to the cat converter where the upper sensor is installed. Anyone out there ever done this ugly and nasty job before? The dealer wants you to sign a 2nd mortgage and give them your first born to do this job ..Ugly !!!

 

Actually I believe the sensor is working since fuel trims are what they've always been.. My Icarsoft I930 reports that the heater circuit has failed open or short circuited DTC1647. The check engine light comes on when the car is started and if I clear it with the scan tool while engine is running the CE light goes off and does not come back on until the next time the care is started.So it looks like the ECM checks the heaters only at start up and once the CE is cleared it doesn't check the O2 heaters again until the car is shut off and then restarted

 

Need to change the sensor then . . . ain't a fun thing, need to remove lots of stuff in the way. There are a couple of threads that describe the process. I said, 'nuff' and took it to my indy who had done many.' Their knuckles were experienced and hardened!

 

As required & as documented.

Just change the sensor.

 

if you are going to replace yours, just stick this stuff between gearbox and exhaust pipe and you will be done within minutes and without all that suffering waiting for you on the top of the engine
you need about 50cm in wrench extensions and large breaker to leverage the wrench

 

Thanks for the info.....while under the car can you see where the connector plugs in ?

 

not really, sockets are on the top of bellhousing away from view and reach, but are easily accessible from the top, A bank side, if you first unscrew and pull aside black box thing that stands on the way