Canon imageRUNNER ADVANCE C5255 Series Service Manual page 657

Item Check item
(2) Relay PCB
J421
Riser PCB
J104
Check for any trapped cables and short circuit between J421 of the Relay PCB and J104 of
the Riser PCB.
1. Disconnect the connectors of J421 and J104.
2. Check if power is distributed between all pins of J421 connector and all the corresponding
pins of J104 connector. Normal value: 0 ohm
<In case FU10 or FU11 on the Relay PCB is blown out>
3. Check for any trapped cables and short circuit between pin 1 of J421 connector and all
the pins of J104 connector (except for the corresponding one), as well as between pin 1 of
J421 and the chassis. Normal value: ∞ ohm
4. Check the rest of the pins of J421 connector in the same manner as step 3.
6
Troubleshooting > Startup System Failure Diagnosis > Flow E: 12V Power Supply System Flow > Flow for narrowing down troubles
Location
J421
J104
6 Troubleshooting > Startup System Failure Diagnosis > Flow E: 12V Power Supply System Flow > Flow for narrowing down troubles
Check the output from the AC Power Supply
Item Check item
(3) AC driver
pins 5 - pins
7
Normal
value:
AC power
(e.g.115 V -
230 V)
AC driver pins 5 - pins 7 (Normal value: AC power(e.g.115 V - 230 V))
T-6-28
Location
J1004 pins 5 - pins 7
6-119
6-119