Trouble Shooting; Power Supply - Canon ELURA10 A Service Manual

7. Trouble Shooting

To detect the failure part for repair, if any, use the following hints and check points.

7-1 Power Supply

<Hints>
When the power source is attached, the unit enters the standby mode in the following sequences.
Power source inserted→ POWER UNREG is supplied to MAIN P.C.B. → SUB microcomputer is activated.→ SUB microcomputer
activates recorder power supply.→SUB microcomputer communicates with MAIN microcomputer.→MAIN microcomputer initializes
the mechanisms.→After initialization, SUB microcomputer turns OFF recorder power supply.→ Standby mode is set.
Then, the power is turned on in the following sequences.
Power mode switch operated → After received at SUB microcomputer, VTR or CAM ON "H" signal is output. → PWM driver is
activated to turn on each power supply. → Each microcomputer (SUB, MAIN, CAMERA) is started up to carry out system control.
<Check Points>
1) Key Inputs
Check the key inputs at Power Switch in the SERVICE mode.
2) Check of microcomputer-to-microcomputer communication
If the microcomputer-to-microcomputer communication line is normal, the version number of each microcomputer can be indi-
cated in the service mode. Otherwise, the communication line or microcomputer may be faulty.
3) Error in Mechanism (P. 3-6)
If any error is occurred by mechanism trouble at initializing, the error can be detected.
At this state, the power can be turned on, but the unit enters "ERROR STOP" state. In this case, check the error data in the
SERVICE mode.
4) VTR ON "H" (control signal from SUB microcomputer) Outputs
Check the output of control signal by the LANC remote controller.
5) Fuses on the POWER SUPPLY P.C.B.
Check the continuations of fuses FU 3201,3202 on MAIN P.C.B. If any fuse is faulty, replace it and check the current consump-
tion.
6) Replace the MAIN P.C.B. with a service part and check the operation.
CAHPTER 3. INFORMATION FOR REPAIR · SERVICE HINTS
3-10
ELURA20 MC A, ELURA10 A