Access the Timer
Unplug the Whirlpool dryer power cord from the dryer electrical outlet. The timer is inside the control panel on the top of the dryer. Pull the dryer away from the back wall so that the control console can be raised without hitting the wall.
Remove the single screw on each end of the control console that secures the control console housing to the top of the dryer. Grab the sides of the control console and raise the front of the console up and toward the rear of the dryer. With the control console in the service position you will now be able to test the timer.
Test the Timer
Locate the dryer timer inside the control console. It will be directly behind the dryer timer control knob. There are two wires that connect from the dryer to the dryer timer. Place a piece of masking tape on each wire and write on the tape what terminal each wire attaches. Use a pair of needle nose pliers to remove the wires from the terminal ends on the timer.
Set the scale on a volt-ohm meter to the RX1 setting to measure the ohms of the timer. Place one probe to one terminal and the other probe to the remaining terminal. You should get a reading between 2,000 ohms and 3,000 ohms. If you do not get this reading, replace the timer.
Replacing the Timer
Pull the control knob off of the timer shaft on the face of the control console. Remove the two screws that secure the timer to the inside of the control console. Pull the timer out and take the timer with you to an appliance repair facility. Compare the new timer to the old timer to make sure that the mounting screws match.
Place the new timer inside the console and secure the timer with the two retaining screws. Attach the wires to the timer and remove the masking tape from the wires. Lower the control console and reattach the console to the top of the dryer with the retaining screws. Push the control knob back over the timer shaft. Push the dryer back against the wall and plug the power cord back into the electrical outlet.