For Technical Assistance Please Call Toll Free 1-877-4BROTHER Wiper Problems There is a popular misunderstanding that the wiper actually cuts the thread. This is not true at all. If it did, how would it cut the bobbin thread as well? Another name for the wiper is “Upper thread guide hook”...
Wiper error when turning on the machine or after a trim and the wiper extended caught the thread and retracted all the way Upper arm cushion is cracked; missing or the screw has broken off causing the solenoid sensor plate to be past the sensor. (See Wiper Assembly Parts Breakdown) Wiper solenoid arm setscrews on the solenoid are loose or missing.
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.
Wiper Assembly Parts Breakdown...
Checking the wiper solenoid Disconnect the wiper solenoid from the machine by following the cable out of the solenoid and unplugging at the connector on the machine. With an ohmmeter measure the resistance across the two pins of the solenoid connector that go to the solenoid. A good solenoid will measure approximately 23 ohms.
Checking the thread guide solenoid base, thread presser base, and wiper holder plate. Thread Guide Solenoid Base Move the solenoid arm in the direction of the arrow with your finger. The upper thread guard hook (wiper) should move easily. If not loosen the three mounting screws and rotate the thread presser base until it does.
Checking thread guide solenoid base Check for a deformed pin on the positioning spacer, B. Also check the thread guide solenoid base at the very bottom to see if it has a bump. A damaged or missing lower arm cushion usually causes this.