O2 sensor troubleshooting

Anyone have a wiring diagram on the air fuel mixture sensor (o2) for an 03 Tacoma 4 cylinder 2wd.

I've been through 2 sensors (both new) and still get the CEL P0135 for my upstream sensor. I have power at the jack with the key on, just don't know how to troubleshoot any further.
Code was cleared multiple times and keeps coming back

Any tips would be appreciated.

 

What kind of sensor are you using? Hopefully not Bosch

 

Denso on both

 

I'm not familiar with 1st gen wiring. But make sure you don't have any blown fuses. That's heater code, so a heater fuse may have popped from a previously faulty sensor

 

I did a bunch of research and I didn't find anything on a air fuel sensor heater fuse. I swapped out the 2 relays in the engine compartment fuse box and it didn't fix the issue so I know those relays are good.

 

The wiring on the cars plug side still looks brand new, no rust underneath or corrosion on the plug. I've searched for a wiring diagram and some troubleshooting steps for an hour and every link I find to wiring or where to look to troubleshoot doesn't work

 

When I get home I'll try and pull up a schematic on alldata

 

Awesome!! I'd appreciate that. I had a password to all data last year but it expired

 

If the schematic I have is correct

Terminal 2 (white/red tracer) should be constant battery voltage when engine is running
Terminal 1 (white) is the ground control from the ECM.

 

Awesome, thanks.

So I have the 12v with the key on at the one connector spot. When testing the ground for the ECM do I put black lead on chassis ground and the other inside the plug and should be reading a ground to determine that wire is good?

Also for the 2 signal wires should I shoot those both together inside the plug and read continuity?

 

Signal should really matter for the codes it's setting. Easiest thing for the ground would be to hook a test light in series with the 12v and the ground since you know the 12v is good.

 

Sorry I'm semi dumb to these things lol. So with my test light hook it up the plug ground and stick the test light lead into the power source and if it lights up I'm good to go?

 

Yes

 

Did that and no light. So assuming no ground to the connector. Any ideas on what to check next?

 

That wire goes straight to ECm. Someother broken wire or bad ecm. I'd be inclined to think it's a wire

 

Wires around the connector look brand new still, hard to really follow it up far with the tight space. I'm going to get a diagram of the ECU and shoot it up that way

 

Anyone know any easy tips on shooting an ECU wire. Require a certain pin puller to remove it?

 

At work, id load test the wire from end to end using the proper test leads that mate to the OE terminals.

 

Anyone have an ECU pin diagram for the 2rz. I can only find the diagrams for the 3rz and 5rz online. Trying to get this pin out so I can shoot the wire.

Thx in advance