gtuttlepi2

HO2S Heater Control Circuit Low Bank1 Sensor1

Let me start off & say that the engine was just rebuilt & when picking up there were multiple codes showing: P1499, P0132, P0138, P0136, P0031, P0051. Got it home & cleared codes & took for drive & P0031 came back.

Not knowing if these O2s have ever been changed I started looking & testing all. Found one downstream O2 had dropped down onto exhaust & had melted itself from sensor to lead from wiring harness. I found how to test these rear O2's & lead wires for power & continuity. I read that the lead wires will have 12v coming from harness because this is how it heats up, the melted one had 1.65v (set 20v) & the good lead wire had NO reading at all.

I pinged the wires up through the wiring harness up to the power distribution center to check fuses/relays etc. The Automatic Shut Down Relay seemed to have continuity, the Rear O2 sensor had continuity & the #16 fuse had continuity. But there is NO POWER coming out of PDC to wiring harness that corresponds to lead wire of one of the rear O2 sensors.

I dont know what to do or where to go now.

Lastly I did check the O2 sensor (4) on ohms & got readings from 011, 019, 015, 015. Are they any good?

PLEASE HELP mechanic wants 500 just to start process

Thank You for reading

gtuttlepi2

tested the relays & they are good & so is the fuse, I traced the wires going to the gray/gray connector & one to the black/black connector & traced 2 wires to the pcm far left module

Does anyone know how to trace from there to see why I am not getting any power to my Rear O2 sensor & also the Injectors fuse has no power to it too

HELP