I live in Canada, we imported a 2003 dodge ram 2500 Hemi from Texas US.
Check engine light was on when we started the truck. The dealer hooked up the scanner and he says that one of my 4 O2 sensors is broken.
I went to a small mechanic shop to do an emission test for this truck so I told him to change the sensors for us.
He said that I only have two O2 sensors on my truck, so he changed 2 of them for some universal. But the problem still exist. So I asked a friend of mine to hook up the scanner for me, and he says that still one is not functioning properly. He reset the code and after driving for a while the check engine light poped up again, so he hooked up the scanner again and it showed him that the second sensor is not working properly, we checked the voltage on the hot running engine of O2 sensor and the voltage shows 0.4 with the book specifications it should be enough but a friend of mine said that somebody was messing around with the wiring.
So my question is, does somebody have a wiring diagram for O2 sensors?
I have one more question. Why does my truck have only two oxygen sensors and everybody says that has to have four.

Please help .

THANK YOU IN ADVANCE.

 

The Dodge wiring diagram's are on this site, worth a shot.

http://www.summitvista.com/hemi

 

there's 2 different O2 sensor setups...the Federal Emissions requires only 2 O2 sensors, while the California Emissions require 4 O2 sensors...it all depends on engine configuration and emissions package....easiest way is to crawl under there and take a look

 

03's have one cat and 2 sensors. 04's have two cats and 4 sensors.

Maybe the universals that he put in are not compatible. Should have went with OEM.

As far as a diagram, tell me if you have 2 or 4 sensors, then tell me which sensor you need the wiring for, depending on the code.

If I don't see this post, email me.