Hi all, new guy here. I have a 1999 Accent that will not start. It is not getting the ground signal from the ecm to the fuel pump relay or the engine control relay. I have swapped ecm's with a known running vehicle of the same year and ecm part# and still no start. This wire is yellow/white and is terminal #1 on the ecm. Does anyone know what tells the ecm to ground that circuit or is there a wiring diagram for the ecm available? I have signed into hyundaitechinfo.com and they do not have the information. Any and all help is greatly appreciated. Thank you. Owen

 

The ECM can self-disable. The salvage replacement ECM may also be disabled. You may not have a good ECM unfortunately.
The ground to the engine control relay is controlled by transistors inside the ECM. (you already know that this turns the relay on...)
The ECM has several power and ground connections: (test this at the ECM female connector)

Grounds connect to: pins 80,61,3, 78,53,51, (and pins 105,113,94 on certain models which have a different ECM with more than 81 pins)
Power connects to: 63,45,44,14,12,5. Check for this power when the ignition is turned on.
3 ECM fuses check these. Located in engine fuse compartment.

I am trying to get more answers on this problem...
But what you can do is:
1. Check for spark when you crank the car. This is activated by the crank shaft sensor. If there is no spark the sensor may have quit working.
2. Camshaft sensor. If this sensor goes bad, the car won't start.
3. Pull the fuel rack, and check that there is gas getting into the rack. (possible clogged fuel strainer or bad fuel pump)

Schematic Diagrams: Look on You Tube for the accent shop manual. It's free.