That's because you are not familiar w/ the Ohm law. U=RI means if any contact presents a resistance because of corrosion for instance, there will be a voltage drop along the contact. So you have a parasitic resistance along either the relay contact or the relay pins.across the connector.
This is the confusing part. When ignition is on the output from the relay -at the relay and at fuse 6/7 - is 5-6v.
OKI don't hear any switching within the relay.
The white wire I mentioned is what feeds from ignition through fuse 2, becoming the brown power supplied to the main relay. The brown wire has 12v as does its jumper across the relay - I do have 12v where you drew the arrows.
Nop. If you see 0.2V on the ground side of the pump while priming, then the ECU grounds the pump when it should.The pump + lead is constant 12v ignition on, the ECU does the switching through the ground wire. The ground wire at the fuel pump to bat+ shows 12v key off and .2v key on - during priming phase and after.
The ECM appears to be grounding with ignition off and not grounding with ignition on.
I provided the schematic for the pin retrieval. Don't you see it?This all sounds like a ground issue with the ECM but I do not understand how the main relay can be outputting 5.3v under any circumstances when battery voltage is sitting at 12.5.
Side note - where can I find the labeled pinout for the ECM connectors?
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