2002 chevy blazer. I check all the fuses and did not find a blown fuse. i have no power (zero volts) at the 02 sensor when the key is in the on position. I recently replaced the catalytic convertor because it clogged and the vehicle would not drive past 25mph. I replaced the 02 sensor when I originally thought that was the problem :/ so its brand new

I'm having a hard time finding wiring diagrams and pcm diagrams to trouble shoot the wire. the wires disappear towards the transmission and I believe the come up by the distributor but its hard to tell.

I checked the tech articles and found some good info on the 02 but nothing that would lead me to trace the wire.

Thanks


Edit: Here is the link to the info on p0135 which is awesome but all it says is "Thoroughly inspect any circuitry that is suspected of causing the intermittent complaint. Refer to Testing for Intermittent and Poor Connections in Diagrams.



If a repair is necessary, refer to Wiring Repairs or Connector Repairs in Diagrams"
https://blazerforum.com/forum/diagno...plained-26610/

 

take a subscription to AllDataDIY. They have most of the factory manual diagnostics and wiring charts online for your specific vehicle.

 

Yeah I might have to go that route. All I need are the pin outs on the pcm and the wiring diagram. I'm thinking Haynes manual will have them and I can give the Haynes manual to the next owner when I sell in a year or so

 

here's the wiring schematic I found with google.

http://www.justanswer.com/chevy/3he6...rs-bank-1.html

 

Thanks. That's exactly what I need.

 

Save your money on the Haynes, those things are absolutely worthless, unless you need to learn how to change oil. Even then, be careful.


Here is the flow chart straight from the GM "dealer issue" shop manual: https://blazerforum.com/forum/diagno...plained-26610/

 

So my thoughts were power has to run through the fuse box from the computer to the 02 sensor. So this weekend I was going to check continuity from the black wire to the fuse. If there is no break in the wire then I will trace it to the pcm. Sound right?

Now that Ive looked over the schematic, The pink wire comes from the fuse box so its the wire that has power and must have a short or the wires coming from the PCM? I'm kinda confused here because if the wires from the PCM have power, how do they get it and how does the PCM not blow and only the fuse will.

Also the numbers 19 and 25 are they the pins on the PCM?

 

Hey Captain,

The images of diagnostic charts in at least part of the tech help threads (like this one) do not download for me anymore. Are you having any luck with them?

Les

 

The only way they worked if I right clicked and opened them Ina new window

 

Excellent - thank you!