PO135 and PO551 concurrent
These two codes have presented themselves as yellow DTCs.
Facts of the Case:
1)All harnesses and wiring have been tested and all are correct and showing proper values and working nominally. Heater as well as signal and ground.
2) Both O2 sensors have been replaced.
3) Some slippage around the PS pressure switch has been observed but very little.
4) All these share a ground but it was tested and is correct.
5) Fuses and relays have been checked.
Possible conclusion : Bad PCM?
What y’all think?