well i got another ecu and my car still wont start this beast killing me no cracking and fuel pump doesn't come on with key

if i bypass fuel pump ecu pump works fine with key
if i by pass start relay under hood starter wants to crank over

stuff i got into it

New starter
New used ECU (since my had bad caps)
Check wiring harness on motor it fine
NEw starter relay
check all fuses all look good and swapped with new on few for starting stuff just in case


tested key switch is sending start signal

starter relay is not getting start signal




i have no clue where to look... help....

 

bump need help on this

 

So you're saying when you bypass the fuel pump ECU, the pump works, but when you don't bypass the fuel pump ECU, it doesn't work? If this is the case, then it's your fuel ECU, unless that is what you just replaced...

 

ya but my car wont crank it not getting signal to starter relay and i dont know where to look to fix

 

I think this might be it...
https://www.clublexus.com/forums/ls4...n-shifter.html

This is on an LS400 but it is pretty much the same engine.

Hope you get this corrected!

Read the 2nd page...

 

sc400 slide THanks so far for the help

i got to theft ecu and Fryed board i ran wire from fryed parts to pin and car now cranks over