If you powered the fuel pump by bypass the relay, then either the relay is faulty or the
wiring to the relay is faulty or there maybe a fuse that is blown.
When the fuel pump relay coil is energizes, the relay contacts will close to supply power to the fuel pump.
Remove the relay then identify the relay coil connectors, then apply 12volts to these connectors, if the relay clicks then the relay is probably OK unless the relay contacts are faulty and then the fault is in the wiring to the relay coil.
Get a service manual wiring diagram and trace the wiring from the relay connector back to the control box/
ignition.
You can use a 12v globe or a multi-meter to check the relay coil at the relay connector to see if it energizes
Comments:
Oct 29, 2009
- The ECM is a computer, most commonly known as a engine control module or engine management unit.
This computer with its sensors, controls all the functions of the engine Eg. fuel management, ignition timing etc. This computer or another computer may control the ABS, air bag and other systems.
The computer has a diagnostic connector that the mechanic can connect a diagnostic tool that can download from the computer the fault list which identifies any faulty sensors and electronic components as well as performance data. This allows the mechanic to quickly fix faulty components and make adjustments to optimize engine performance.