The programs in the Expander's memory are maintained by two "AA" size batteries on the computer board. Periodically check the battery voltage by pressing [SPECIAL FUNCT], then . If the cell reading in the DATA READOUT is less than 2.5 volts, have your service center replace the batteries. As a precaution, always make a backup cassette tape of your programs in the event your batteries run down before you get to the service center.
When the Expander is first turned on, or when the [AUTO TUNE] switch is used, each of the 16 oscillators and filters are checked and tuned. If any channel fails to function or cannot be tuned properly, an error message will appear in the DATA READOUT.
There are eight Dual Channel Boards in the Expander labelled "0" through "7." When a defective channel is encountered during the tuning process, the channel board is turned off automatically. The Expander will operate normally, but with two less channels. Subsequently pressing [AUTO TUNE] will not affect the disabled board. The Expander's computer is instructed to ignore this board until a power-up or reset occurs.
For example, the message "Err 0" means that channel number "0" is defective and has been disabled. If there is no error, the DATA READOUT will show a "P" or an "L" as the first letter in the display.
Occasionally, a channel may be just slightly out of tune due to exposure to temperature extremes. To retest a channel (to verify that it is indeed defective) press [SPECIAL FUNCT], then . This resets the Expander. This will cause the Expander to go through its initialization sequence which tests and tunes all boards. If the same error message occurs, contact your local service center.
Checking for Disabled Boards
If at any time you wish to see if any of the channel boards have been disabled, press [SPECIAL FUNCT], then . If any channels are turned off, the DATA READOUT will display "Err" followed by the channel number. If the DATA READOUT does not appear to have changed, then all boards are functioning properly.
If a problem should develop on a channel board during performance and is not automatically turned off, it can be manually turned off. First play the keyboard until the offending note is heard. Before playing another key, press [SPECIAL FUNCT]. . This will cause the last channel board to be played to be turned off. The DATA READOUT will display 'Err' followed by the channel number. To turn the channel back on, press [SPECIAL FUNCT]  (reset), or turn the Expander off and then on again.
Under the control panel of the Expander is a mechanical "tapper" which strikes the control panel whenever a switch is pressed. Even in loud music situations, the pressing of a switch can be felt, confirming that the switch has been closed. To turn off the tapper, press [SPECIAL FUNCT], . To turn the tapper back on, press [SPECIAL FUNCT],  again.
If during a cassette load operation faulty data is received, the Expander will halt the tape deck and display "Error." See the Cassette Interface Section of this manual for more information.
|No lights when Expander is turned on.||No power.||Check power cord and switch, verify that the outlet has power.|
|No audio output.||Audio output not connected to MONO OUTPUT.||Put plug in MONO OUTPUT, remove all plugs from the 4 AUDIO OUTPUTS.|
|Volume pedal is used in current program.||Set the volume pedal to maximum, or unplug it.|
|VOLUME slider down.||Raise VOLUME slider.|
|No program in "current program".||Select a different program, or reload cassette, and then select a program. (Also, check battery level.)|
|PROGRAM NUMBER display goes out and Expander will not play.||Computer interruption has occurred.||Turn power off, then on again.|
|Cannot change programs.||Right panel in [PARAM SELECT] or [COPY] mode.||Press [PROG SELECT].|
|Cannot change parameters.||Not in [PARAM SELECT] mode.||Press [PARAM SELECT].|
|When editing, PARAMETER CONTROL slider has no effect.||Wrong [EDIT] switch selected. (e.g., [EDIT B] selected, [EDIT A] required.)||Try other [EDIT] switch, or both [EDIT] switches should be on.|
|MONO OUT EQ sliders do not affect the 4 AUDIO OUTPUTS.||Normal.||MONO OUT EQ sliders only affect the MONO OUTPUTS.|
|[STORE] does not work..||LOCK/UNLOCK switch is in the LOCK position.||Put LOCK/UNLOCK switch in the UNLOCK position.|
|Notes are out of tune.||Channels need tuning.||Press [AUTO TUNE].|
|Oscillator B is deliberately detained in program.||Press [PARAM SELECT], . Change detune value using PARAMETER CONTROL slider.|
|[SAVE ALL] produces short bursts of sound.||Cassette is in "save programs with spaces" mode.||Put LOCK/UNLOCK switch in the LOCK position.|
|Cassette doesn't halt after [LOAD] or [SAVE].||Wrong cassette mode.||Press [SPECIAL FUNCT], .|
|In LINK mode, the MAIN or LINK programs are too low in volume.||Link balance set wrong.||Move PARAMETER CONTROL slider to correct balance.|
|Levers do not work.||Not in program.||Select different program, or edit program to assign lever functions.|
|Volume pedal does not work.||Not in program.||Edit program to assign volume pedal.|
|No "tap" felt when switch is pressed.||Tapper disabled.||Press [SPECIAL FUNCT],  to enable the tapper.|