Chrysler Repair: oxygen sensor, actron scanner, dodge ram 1500

Question
Have a 1997 Dodge Ram 1500 4x4 5.9L V8 with 144k miles. Check Engine light has been on a while. Read the code with an Actron Scanner: 0132 O2 Sensor Circuit High Voltage (Bank 1, Sensor 1). Asked Actron tech which sensor it was referring to, and he said the one before catalytic convertor. Parts house needed to know length of harness so I disconnected the front one to measure and decided to take another code reading. It still picked up the 132 code plus 0138 (left 02 #2 shorted Hi). To me that indicates the front sensor is the #2 sensor and not #1. After reconnecting, goes back to #1 sensor code 0132. Am I right, or did disconnecting the front one give a bad reading on the second one? Don't want to replace them both at $80 each, but I will if I need to. What do you think?  

Answer
Hi Mickey,
I don't have a manual for the 5.9L V-8. However for the 2.5L V-6's the 1/1 (132) and 1/2 (138) are designated to be the ones on the right cylinder bank ("rear" in a transverse mounting situation), up and down-stream, respectively. So I wonder about the problem being on the left (driver side) rather than the right (passenger side). So you might want to see if you can get an official listing of the trouble codes for your engine at a Chrysler dealer.  1 and 2 seem to universally be up and down, respectively, regardless of the engine. I would suspect that by disconnecting the #1 you provoked both the codes for 1 and 2. I would start with changing only the front sensor (on which ever side proves to be correct), then erase the codes by reader or by disconnecting the battery for a few minutes, and then drive it for a while and see what you get on another readout. The upstream sensor usually fails earlier than the rear.
Roland