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Service Code Output Format

Fig. 26 Service code format:




Fig. 27 Time pulse format:





The EEC-IV system transmits its information by the use of the self-test service codes. These service codes are two digit numbers representing the results of the self-test. The service codes are transmitted on the self-test output (found in the self-test electrical connector) in the form of time pulses, and read by the use of a voltmeter or a STAR tester.
The pulse format is (refer to Figs. 26 and 27 as follows:
1. One-half second on-time for each digit.
2. Two seconds off-time between digits.
3. Four seconds off-time between codes.
4. Six to nine seconds off-time before and after the half-second separator pulse.