The power comes from fuse "C" in the engine compartment fuse relay panel and then through the PCM Power Relay in the engine compartment fuse relay panel. In your van both are good or you would have no codes at all and the engine would not run.

Diagnostic Trouble Codes (DTCs) P0135, P0141, P0155 and P0161 indicate a short to ground, open, or short to VPWR in the HO2S heater circuit.

Possible causes:

Shorts to B+ in harness or HO2S.
Water in connectors.
Cut or pulled wires.
Disconnected wiring.
Open VPWR circuit.
Open GND circuit.
Low battery voltage.
Corrosion or poor mating terminals.
Damaged PCM.

I do not know what engine/transmission you have so I can not give you any more information or wiring diagrams/wire locations.



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