My pump relay is getting 12v but the grey power wire to the pump is only get 1.4v. Would not having power to ecm cause the pump to not have 12v?

Should have 12V on the Red wire full time, key ON or OFF
Should have 12V on Pink wire when key is ON

The Red wire goes to the FP relay then changes to Pink/Black after fuse to the relay and supply power to one side the relay main contact (30). One side of the coil is grounded (85), so when the Green/White wire gets 12V (86) from the ECM (J1 connector) it pulls the contact closed and passes 12V (thru Pink/Black wire) to the gray wire (87). Find out if your getting 12V from the ECM on the Green/White

If it is closing then maybe there is no power to the Pink/Black wire


https://cimg7.ibsrv.net/gimg/www.off...701272e841.jpg

That’s some great information. I plan on checking those things tomorrow and I will follow up on here. Thanks for everyone’s help so far

That tells me that the relay is bad. Probably a corroded contact. Either that or the grey wire is almost open somewhere. Is there another relay of the same part number that you can swap it with ? Where are you measuring the 1.4 volts ?

I am assuming that the relay is clicking ?

No corrosion both harnesses are brand new out of a box. The power to pump (grey) getting 1.4v

That’s exactly what I was thinking, or the 12v supply to the relay has a bad circuit and shows 12v until a load is intruduced(fuel pump) and then drops out. Only takes one strand to show 12v on a DVOM but takes a lot more to carry amps.

The 1.4V could just be the meter floating, but relay could be bad.

Unless the motor is running the FP relay will only turn ON for a couple seconds, then back OFF

Put meter on the Green/White at the relay. If there is no power applied from the ECM then the ECM is either not being turned ON (no beep) or ECM is bad, bad connection to ECM, something disconnected

The MPR and FP relay are the same and can be swapped

Is the relay "clicking" ?

Yes I do hear a clicking noise. I will check the ecm power and I have extra relays I can switch out. Thanks for help

If you hear the relay "clicking" then most likely the power from the ecm is fine. I would just swap the relay with another and try it. Quick and simple test.