o2 Sensor code p0140

[arcdodge]

1997 Caravan 2.4L. I have replaced the O2 sensor indicated by code P0140 but the check engine light remains with the same code. (all codes were reset). A local auto parts store had a guide that suggested checking the circuit breaker, fuse or relay. Does anyone know where this might be located. I cannot find one labled for o2 sensor so I am guessing it may be using another or it is undocumented.

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[dishdude2k]

if there is a fuse relay or breaker for it.. its news to me.. need to check all wiring.. and make sure you replaced the right o2 sensor

and if its the front o2 sensor giving you problems.. might want to make sure the cat isnt plugged up.. that will also trigger the c/e light on that code.. the o2 sensor is just doing its job.. do you smell rotten eggs while driving? lack of power? 'putting' ? all signs of a plugged up cat.

[arcdodge]

It was the rear sensor that was replaced. I've not had bad exhaust smell or lack of power (other than it is a 2.4 litre).
The wiring goes into a hole up into the chasis, so very difficult to follow. There isa rubber grommet that holds the wiring securely in place in the hole which when I removed the old one, there was quite a bit of water which came out.

So if there's not a fuse or relay involved then where should the wiring lead to. The PCM?

[dishdude2k]

thats correct..it will go to the pcm.. in a long roundabout way.. those sensors report back to the pcm and the pcm will decide on the rest... i would pull the other o2 sensors and clean em up real good.. then put em back in.. see if it helps.. you might just find a burned up wire on one of them

[arcdodge]

OK Thanks. At least I now know I'm not trying to track down a relay or fuse. I'll replace the other sensor and triple check all connections. Probably won't be until next weekend but I'll let you know what I find out.
Thanks for the advice.