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Central Timer Module Diagnostic Trouble Codes

The Central Timer Module (CTM) Diagnostic Trouble Codes (DTCs) are two digits in length and are output to the operator by the sounding of the chime.







The first digit is output, followed by a one second pause, followed by the next digit. Each digit is made up of one to nine one-second individual chime tones. The above represents the output of the DTC 21.