Goodman MBE Series Installation Instructions Manual page 23

A test lead or jumper wire can be added from the test terminal
to any terminal on the B13682-74 or B13682-71 variable speed
terminal board and provide information through the use of the
LED lights on the B13682-71 VSTB control. Using this chart,
a technician can determine if the proper input signal is being
received by the encoded VSTB control and diagnose any prob-
lems that may be relayed to the output response of the B13682-
74 VSTM control.
Example:
st
The system is calling for 1
input signal from either thermostat option will cause the red "+"
LED light to illuminate when the test terminal and the "S1"
terminal are connected using a test lead or jumper wire. This
verifies proper input from the thermostat. The proper output is
a "YCON" signal to the RSG condensing unit. When a test
stage cooling operation. The proper
lead or jumper is connected between Test and YCON, the red
"+" LED will illuminate. The corresponding response from the
CKTS control will be an illuminated "LOW" LED light and 24V
applied to the Low capacity contactor through the "LOW" ter-
minal output.
This similar procedure can be utilized on any terminal on the
VSTB controls. The chart above indicates the proper input and
LED status as well as the corresponding out signal. Each
mode of operation must be verified during the check out proce-
dure when the units are installed. The LED light provides a
easy method to verify operation without the use of a multi-
meter.
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