Bernina 135 S appendix Trouble shooting

62 Faults

Trouble shooting

In most cases you will be able to identify and remedy faults by checking the following.

Check whether:

•the upper and lower threads are threaded correctly

•the needle is inserted correctly

•the needle size is correct – check the needle/thread table p. 57

•the sewing computer is clean – brush out any thread fluff

•the hook race is clean

•any threads are trapped between the tension discs or under the bobbin case spring

•the bobbin runs smoothly in the case or if remnants or lint need removing

Skipped stitches

• Wrong needles used.

Use only 130/705H system.

• The needle is blunt, bent or

incorrectly inserted.

• Push right to the top when

inserting.

• Needle inserted all the way

to the top.

• The needle point does not

suit the fabric being sewn.

Faulty stitching

• Remnants of thread between
	the tension discs.
• Remnants of thread under
	the bobbin case spring.
• Lower thread still threaded in
	the bobbin case finger.
•	Sewing computer threaded
	with foot down.
•	Incorrect threading. Check
	upper and lower threads.

Upper thread breaks

•The upper thread tension is too tight.

•The needles are of a poor quality. Ideally needles should be purchased from your BERNINA dealer.

•The needle is bent or blunt.

•Poor quality, knotted or dried out thread has been used.

•Use the correct spool disc.

•Stitch plate or hook tip damaged. Take your sewing computer to your BERNINA dealer.

Lower thread breaks

•The lower thread tension is too tight.

•The bobbin is jamming in the bobbin case. Remove and replace the bobbin.

•The hole in the stitch plate has been damaged by the needle. This must be repolished by an expert.

•The needle is blunt or bent.

If necessary use a ball point

for knitted fabrics and

cutting point for hard leather.

Needle breaks

•Needle clamp screw loose.

•Fabric taken out in front instead of behind presser foot.

•When sewing over thick area, the fabric was pushed with the needle still in the fabric.

•Poor quality thread, unevenly wound or knotted.

•See pages 56 and 57 for information about needles

• Use the correct spool disc.

Sewing computer fails to run or runs slowly

•Plug not properly inserted.

•Power switch in off position.

•Sewing computer has been standing in a cold room.

•Bobbin winder still switched on.

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