Denso BHT-400B-CE - Manual (Page 154)

4.1 System Errors
If some error occurs when the power is turned on or during program execution, one of the following error
messages will appear on the LCD.
System Program error
Problem
A System Program error has occurred.
If this error occurs, the BHT beeps five times (for 0.1 second per
beep) and then turns itself off.
Solution
Contact your nearest dealer.
Low battery warning
Problem
When the power is turned on or off or during execution of
applications, the battery output level has dropped below the specified
lower level limit.
If low battery is detected, the BHT displays this message for
approx. 2 seconds and beeps three times (for 0.1 second per
beep). After that, it will resume previous regular operation.
Solution
The battery cartridge will need to be recharged before long.
Replace or recharge the battery cartridge. (For the charging
procedure, refer to Chapter 5, Section 5.5.)
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