Brother BAS-416 Manual page 3

Wiper comes down but does not retract
Slot in thread guide solenoid bracket base needs to be lubricated. Apply
black grease in the shaded area of the Wiper Assembly Parts
Breakdown.
Magic tapes in thread presser base assembly are either missing or
damaged. (See Wiper Assembly Parts Breakdown)
Thread presser base misadjusted or bent. (See checking thread presser
base and cover alignment)
Spring is stretched, missing or not hooked correctly. (See Wiper
Assembly Parts Breakdown)
Nut on positioning spacer, B is either loose or missing. Apply thread
adhesive to thread to prevent nut from coming off. (See Wiper Assembly
Parts Breakdown)
Thread guide solenoid bracket base is misaligned or scratched at the
bottom of the slot. (See checking thread guide solenoid base)
Lower arm cushion is cracked, missing or the screw has broken off
causing the positioning spacer, B to damaged the bottom of the thread
guide solenoid bracket base. (See Wiper Assembly Parts Breakdown)
Bent presser foot
Wiper holder plate is bent or not adjusted correctly. (See checking wiper
holder plate)
Wiper comes down and retracts but does not grab the upper thread.
Nut on positioning spacer, B is either loose or missing. (See Wiper
Assembly Parts Breakdown)
Upper thread guide hook is not adjusted correctly. (See Wiper holder
plate adjustment)
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