Brother KE-430B Service Manual page 196

8. ELECTRIC MECHANISM
Error status #20 The machine does not stop with the needle at the upper position.
("E-50" appears <"E.22" for the KE-436B and 436C>.)
Probable causes
3. Cord defective
4. Power supply circuit board
defective
Main circuit board
+15 – 18V for each
5. Main circuit board defective
6. Motor defective
Error status #21 Programming can not be made. (KE-436B, 436C only)
Probable causes
1. The programmer connector
and its cable are defective.
2. The programmer is defective.
3. Panel circuit board defective
189
Check/ repair/ adjust
• See #15-1.
• With P13 (DC18) connectors plugged in
on the main circuit board, measure the
voltage in the connector on the cable.
If the voltage across the following pairs of
pins, pins 1 and 2, pins 4 and 5, and pins
10 and 11 is DC 15–18 V, it is OK.
3651Q
Check/ repair/ adjust
• Remove connector P2 (PGM) on the
panel PCB and connector P2 on the
programmer PCB, and then return them to
their positions.
• Replace the programmer with a new one.
• Replace the panel circuit board with a new
one.
KE-430B, 430C series
Parts to be replaced
Power supply circuit
board
Main circuit board
Motor
Parts to be replaced
Programmer
Panel circuit board