Jackson MSC JP-24B Service Manual - Service Procedures Continued
SERVICE PROCEDURES continued
Function of each of the cam micro-switches starting from the timer motor.
CAM NO 1 - C-1 Cycle cam/Reset cam which is not adjustable, controls the total length of the cycle. It is
activated by the door switch when the door of the dishwasher is opened and closed.
CAM NO 2 - C-2 Cam not adjustable. Controls the draining of the dishwasher when the Off/Drain switch is
depressed. It powers the drain valve to open at (85) seconds into the dishwashing cycle.
CAM NO 3 - C-3 Cam not adjustable. After (3) second reset, cam switch powers wash pump motor for (82)
second wash cycle and then remains on for additional (18) seconds for drain and dwell.
CAM NO 4 - C-4 Adjustable cam. Controls power to the drain valve to drain the wash tank by. The cam is
factory set to open the drain at 85 seconds into the dishwashing cycle and close at 101 seconds.
CAM NO 5 - C-5 Adjustable cam. Controls power to the fill solenoid valve. Cam is factory set to open (106)
seconds into the cycle and close at (116) seconds. At (20) PSI flow pressure; this allows the required
quantity (1) gallon of water to flow into the dishwasher. If the flow pressure is different than 20 PSI or if
drain time has been changed, the fill time will need to be increased or decreased sufficiently to allow the
dishwasher to operate with a minimum of (1) gallon of water.
CAM NO 6 - C-6 Adjustable detergent cam. It operates the aftermarket dispenser/feeder pump that injects
detergent. Cam is factory set to duration of (8) seconds to dispense approximately (15) milliliters of
detergent. By adjusting the right side of the cam, you can either increase or decrease your amount of
detergent.
B. To check the timer control.
(1) Place cycle switch to Auto, close door to start dishwasher.
(2) Check advance of timer. If it doesn't rotate, REMOVE POWER TO DISHWASHER and check
continuity of timer motor. If OK, restore power and check for voltage at timer motor.
(3) Turn cams manually slowly through cycle. Listen for operation of wash motor, draining and rinse
solenoid valve.
(4) If a component fails to operate, REMOVE POWER FROM DISHWASHER and check continuity
of component. If OK, restore power and check to see if voltage is being delivered to component
from timer.
C. To replace the timer cam switch.
(1) Remove all wires from cam switch and note wire locations.
(2) Remove cam switch which is secured in place by (1) phillips head screw. Slide switch to the rear
and off frame.
(3) Install replacement switch in reverse order. Note: Insure switch is positioned into notch in frame
of timer.
D. To replace the timer motor.
(1) A defective motor is indicated by the fact that the cams do not rotate or the machine does not
perform the automatic functions, but works in manual.
(2) Disconnect motor wire leads.
(3) Remove the motor which is secured by (2) screws.
(4) Replace motor and install in reverse order of above.
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