If your remote is losing the presets, you need to replace the battery.

1. Remove 6 screws on the front of the unit. There are 4 on the left and 4 on the right hand side in a vertical row. Remove the first two and the last one on each side, leaving the one near the middle, these will be removed later. [See Pic 01]

2. Remove the 2 screws on each side of the unit and the screw near the top center of the front.

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3. Remove the cover slowly, there may be a connector to a voltage regulator chip on the back of the cover. If so, unplug the wires, remembering which way to plug back in when assembling the unit.

4. Remove the small 2/56 screw and nut that secures the top 8 pin Din connector to the front panel.

5. Remove the two middle screws mentioned in step 1 on the front of the unit. Then remove the 6 nuts holding the circuit board to the standoffs using a 1/4 " nut driver or similar tool. Under the nuts are plastic washers, remove them at this time, they tend to get lost when removing the circuit board. [See Pic 02,03, 04]

7. Slowly lift up the top circuit board, there are connecting wires underneath. Facing the front of the unit, unplug the connector on the right hand side under the top circuit board, remembering which way it is oriented in order to plug it in correctly when assembling the unit.

8. The top circuit board can now be lifted up and tilted to the left being careful not to unplug the other connectors. [See Pic 05]

9. Lift up the strap holding down the battery, remove the old battery, checking the battery case for any residue that would prevent a good connection, and replace the battery with a new CR2032, 3 volt Lithium battery. [See Pic 06]
10. Reassemble unit and pray that it works.

You should get 5 years out of a new battery.