First off want to say that someone else figured this out,not my idea, but it was too good to not share on here. Back in about 04-05 I had my catalytic converter sawzall'd off and stolen. On comes the check engine light. Didn't think to much about the light being on because I knew what it was after a very short period of time. Climbing a steep grade with a load and putting more heat on the system, the light would go off. Once crested the hill and things started to cool off,,the light would come back on. Rear O2 sensor sending the signal that something was amiss. Truck never gave me any problems so no need to by a code scanner and I knew what the CEL light was from. (For the sake of arguments, lets say I had a really good idea why the light was on). Anyways,,here we go.
Radio Shack part #
1 micro farad cap 272-1055
1 mega ohm resistors 271-1134
On my truck there are 4 wires that lead to that rear O2 sensor from the connection plug at the manual transmission tail shaft. 2 black and a sold white and solid blue I split the distance in the length of those blue and white wires and cut them in two at the center. You will probably have to pull back or remove the tubing/covering that covers those wires. I slit that cover down the center with a razor to about 1/2 distance, then cut around it, removing that portion. Snip and strip back the blue and the white wire that leads forward to the connection plug,,I left the two black wires intact and connected to the sensor. The reason I cut the blue and white wires at equal lengths between connection plug and sensor,,was so that they could be easily reconnected again if needed.
As you see the pic above of the constructed Mod unit(),,the right side of the unit connects to the blue wire you cut and stripped back a 1/2",,and the left connects to the white wire that you also prepared the same way. (connection plug side)
Assemble the unit as you see in the pic noticing lettering up on the blue capacitor and color rings on the resistor. Right side of assembled unit connects to the blue wire, and the left side of above pic connects to the white wire.
You can solder connections if you wish, or you can crimp connect so long as you have good crimping tools and supplys. I did a little of both. A bead of silver solder was melted by iron down into the bottoms of those crimp connectors you see above. The unit was then crimped and soldered to the prepared blue and white wires down by the sensor that lead to the plug connection
Snipped white and blue wires leading to the sensor were covered with heat shrink tube. I didn't pull any connection plug or the sensor out of the pipe,no real need because I had the wire length I needed.
Total cost to turn out the check engine light due to a rear O2 sensor code,,about $4.
Pull battery connections BEFORE you start cutting. Not a bold typed set in stone rule,,but It's the way I did it. The ECU will need a reset anyways after doing the work.
I'm no electronics expert so keep the questions with that in mind.