Sam4s SAP-630 Series - Power problem

6 Troubleshooting
6-2 SAM4S SAP-630 SERIES
6-2 Power problem
6-2-1 Verifying the power supply
 Checking AC power cord.
 Checking the power switch whether it is connected well.
 Separate the power harness between SMPS and MAIN B’D.
And measure the DC output voltage on SMPS (+24V)
 If it does not go out, please replace the SMPS.
 If it output voltage is ok, check next.
6-2-2 Verifying the MAIN B’D power line
 Checking the power 5V LED on MAIN B’D (LED1), if it is on or not.
 If the power 5V LED are off, It must be short between power line and ground. (+V5S)
In this case, power off and separate the SMPS, MAIN B’D, LCD B’D and measure the resistance
between power line and ground.
 Measure other voltage.(Ex : VDD3.3V, VDD1.8V, Vserial)
 If these voltages above mentioned do not go out, check the appropriate regulator or component.
And check power line is short or open.
6-2-3 Verifying the LCD B’D power line
 The LCD B’D source voltage (VDD5V) is supplied the IO B’D
 Checking the power LEDs on lcd B’D, if it is on or not.
 If the power LEDs are off, It must be short between power line and ground. (VDD5V)
In this case, power off and measure the resistance between power line and ground.
 Measure other voltage.(Ex : +V3.3S, LCDVDD, VLED+)
 If these voltages above mentioned do not go out, check the appropriate regulator or component.
And check power line is short or open.
NOTE :
During servicing & repairing, Be careful against receiving an electric-shock.