GE Giraffe Blue Spot PT Lite - Page 58

58
Chapter 10: Diagnostics and Troubleshooting
ID Symptom Description Possible Causes Actions & Solution
S1
When system is in
standby mode (plugged
into power outlet and
standby/on switch is not
pressed yet), BOTH the
standby/on indicator and
hour meter display are
o.
(Normally, when the
system is plugged into
a power outlet, the
standby/on indicator is
green and the hour meter
display shows an hour
number.)
Power cord is not
properly connected.
Conrm that the power cord is plugged into the power
outlet and securely connected to the power inlet module
of the system.
No power at the
outlet.
Conrm power is available at the power outlet.
Fuses are open
(defective) or
missing.
Refer to section 10.1.
A system wire
harness is
disconnected.
Remove the unit cover and check whether all the wire
harnesses are properly plugged and connected. Refer to
section 11.5.
Power entry module
is defective.
Remove the unit cover and measure the AC input to
the power supply. Replace the power entry module if
necessary. Refer to section 11.6.
Power supply board
/ LED driver board is
defective.
Remove the cover and measure the voltage between
GND and -12V test points on the LED driver board using
a multi meter. Conrm if the voltage is within the -12V +/-
0.15 range. If not, remove the AC power and then unplug
the DC harness coming from power supply board at LED
driver board side. Restore AC power and then re-measure
voltage at the harness connectors. If the voltage is now
within the range, replace the LED drive board (Refer to
section 11.7). Otherwise, remove the LED driver board
and: a) disconnect the DC harness from the power supply
board and perform the wire continuity test on the harness
to conrm the harness is not defective. Replace the DC
harness if necessary. b) with the DC harness disconnected
from the LED driver board, use a small screw driver to set
the power supply output voltage to be within the -12V +/-
0.15 range by adjusting R13 potentiometer on the power
supply board. If the output voltage cannot be set, replace
the power supply board (Refer to section 11.8).
NOTE: The power supply board has internal short circuit
protection that could be limiting the output voltage due to
a short circuit in the load (LED driver board).
LED driver board
/ Control board is
defective.
Remove the cover and measure the voltage between
GND and V+ test points on the LED driver board using
a multi meter. Conrm if the voltage is within the 5V +/-
0.3 range. If not, remove the AC power and then unplug
the control harness from the control board. Restore AC
power and then re-measure the voltage between GND
and V+. If the voltage is still outside of the range, replace
the LED driver board (Refer to section 11.7). Otherwise, a)
disconnect the control harness on both ends and perform
the wire continuity test on the harness to conrm the
harness is not defective. Replace the control harness if
necessary. b) If the harness is not defective, replace the
control board. Refer to section 11.5.