How to Troubleshoot an Intermatic T104M

Verify the dial rotates. If it does not, check the wiring to the timer to see that the load and line connections are not reversed at the terminal screws. Replace the clock motor, if necessary.

Replace the trippers on the dial face if the dial rotates, but switch works only in the override mode. Also check the wiring connections to the terminal screws are secure.

Determine whether the timer keeps correct time. If a power failure occurred recently, reset the clock. The breaker that controls the timer should be operational. Look for loose wires at the terminal connections.

Replace the trippers if the timer turns the switch on but not off, or off but not on.

Turn the manual override, if the timer does not turn the power on and off automatically. If the manual override does not turn the power on either, check the power source and the controlling breaker. Verify there is voltage output to the load at the terminal connections.

Check the wiring connections if the dial stops rotating only after passing the tripper.

Check for free movement of the dial and override lever. If it feels sluggish or sticky, turn off power to the timer and spray the clock mechanism gears and the override lubricant with manufacturer-recommended spray lubricant.