First, make sure the ECU you got has the same part number. If it is different, it will not work properly. Since everything has been checked, I still feel the problem is in the wiring between the ignition switch and the relay. You could have an internal break in the wiring that cannot be seen. As a result, continuity needs to be checked through the power supply wires.
I have attached a schematic of the starting system for you to look at. There are a few things I need you to check. First, from the positive remote (under the hood) power is supplied to the ignition switch via a red wire. Check at the switch to make sure it is hot. From there, it follows a yellow wire to the PCM crank fuse (10 amp). Make sure it is not blown and make sure you have power in that wire with the key in the start position. After the fuse, the wire in question is purple and runs to the PCM crank request/crank relay control in the air box (check for power). If there is still power, the wire to follow is yellow with a black tracer which runs to the under-hood junction block (pin C10). (check for power) From there, power comes out from a purple wire (pin B10) and goes to the starter solenoid. Check for power. Keep in mind, the purple wire actuates the solenoid and energizes the starter. However, the true power to the starter (to turn it) is always hot. It is the big wire directly from the battery. Also, all of the places I said to check for power needs to be done with the key in the start position, and there should be twelve volts present. If you have power throughout the map I sent you, the starter system has been checked. Which leads me to the next question. Are all the wires in the junction block (under the hood) clean, tight, and not corroded?
Sorry this is so long, but it takes awhile to explain it all. Also, I want you to let me know if the vehicle has a factory remote start system. Finally, when you are checking for power, make sure to move the wires around to make sure power continues to flow and not stop.
See where you are losing power
Check out the diagrams (Below)
Let me know what you find.
Images (Click to enlarge)
Wednesday, March 16th, 2011 AT 4:17 AM