Samsung SCX-8030ND Series Service Manual page 426

● Symptom
The keyboard does not operate.
● Possible cause
1. Keyboard is defective.
2. OPE is defective.
3. HUB PBA is not supplied with power.
● Troubleshooting method :
1. Replace the keyboard. Check its operation again.
2. Replace the OPE. Check its operation again.
3. Check if power is supplied to the HUB PBA.
4. Replace the engine controller.
5. Replace the DC relay PBA.
7.4.2 USB port problem
● Symptom
USB port on front side does not work.
● Possible cause
1. HUB PBA is defective.
2. Power is not supplied to HUB PBA.
● Troubleshooting method :
1. Replace the HUB PBA. Check its operation again.
2. Check if power is supplied to the HUB PBA.
3. Replace the engine controller.
4. Replace the DC relay PBA. p
Service Manual
SCX-8030/8040 series
7.Troubles
y
shooting
7-1 33
SAMSUNG ELECTRONICS
Version 0.05