I could not find info on the given model number.
The following is a unit with the "Y" removed.
The Y often designates a non US unit and there may be small differences in the wiring.

Here are the parts
Replacement parts for WHIRLPOOL RAX6144EQ1 | AppliancePartsPros.com

Here is the wiring diagram
http://www.servicematters.com/docs/wiring/Wiring%20Sheet%20-%203948835.pdf

Unit should not start with out the unit filling so two possibilities come to mind, the water level switch or the timer.

When the unit will not fill, unplug it. Remove the V wire from the water level switch and measure across the switch. V connector to T should be infinite ohms and V to P should be 0 ohms. If not the switch needs replacing as it is sticking in the actuated position so the unit thinks it is already full of water.
Be gentle when doing this as just a slight bump may cause the switch to unstuck.

If the water level switch is OK then odds are the timer is the problem.

[COLOR="Blue"]Is the part you linked to my is the timer ??[/COLOR]
The timer is Item 9 in Section 2.

[COLOR="Blue"] if yes may I have the exact model number.[/COLOR]
I am not sure that it is the correct part as I cannot find any parts for a unit with a Y at the beginning.
Best to call/email the people at AppliancePartsPros to be sure you get the correct timer.