---
title: "BAI Embroidery Machine Troubleshooting: Panel Errors, Thread Breaks and Fixes"
description: "BAI embroidery machine troubleshooting for THE MIRROR and THE VISION: Institch i5 panel faults, thread breaks, birdnests, limits, oiling and settings."
url: https://easydigitizer.com/troubleshooter/bai
updated: 2026-10-14
brand: BAI
class: commercial
origin: China
formats: DST (native), DSB
data: https://easydigitizer.com/troubleshooter/data.json
agent_playbook: https://easydigitizer.com/troubleshooter/agent.md
publisher: EasyDigitizer (https://easydigitizer.com/)
---

# BAI embroidery machine troubleshooting

BAI embroidery machine troubleshooting for THE MIRROR and THE VISION: Institch i5 panel faults, thread breaks, birdnests, limits, oiling and settings.

> **Short answer:** Most BAI stops are fixed by rethreading the needle that stopped from the cone with the thread fully in the tension discs, fitting a fresh needle the right way round, and oiling the machine on schedule (twice a week, three times a week on long shifts). The panel fault you will see most is **Main axis not in 100°**: turn the handwheel (or use the panel jog) until the main shaft is back at 100°, then restart. BAI does not publish numbered error codes; the Institch i5 panel shows named faults, listed below.

## Model families
### THE MIRROR
- **Type:** Commercial single-head, 15 needles
- **Years:** Current
- **Field:** 500 × 350 mm
- **Max speed:** 1,000 spm
- **Panel:** Institch i5, 10 in. touchscreen, USB and Wi-Fi
- **Formats:** DST, DSB
- **Manual:** [BAI download center (catalog, Institch i5 manual, maintenance and repair tips)](https://www.ibaima.com/download-center/)
- **Tags:** single-head, cap, 15-needle, laser, entry-level
BAI's entry machine for start-ups and home businesses. It ships with a cap driver, cap frames and a hooping station. Typical problems are threading mistakes, needles fitted the wrong way, and skipped oiling.

### THE VISION
- **Type:** Commercial single-head, 15 needles
- **Years:** Current (product code EOC06)
- **Field:** 400 × 500 mm
- **Max speed:** 1,200 spm
- **Panel:** Institch i5, 10 in. touchscreen, USB and Wi-Fi
- **Formats:** DST, DSB
- **Manual:** [BAI download center](https://www.ibaima.com/download-center/)
- **Tags:** single-head, cap, 15-needle, laser, production
BAI's production single-head, sold for hat and apparel shops. It runs faster than the Mirror, so worn needles, dry hooks and the wrong cap settings show up sooner.

### THE VISION-2 (two-head)
- **Type:** Commercial multi-head, 2 heads × 15 needles
- **Years:** Current
- **Panel:** Institch i5, 10 in. touchscreen, USB and Wi-Fi
- **Formats:** DST, DSB
- **Manual:** [BAI download center](https://www.ibaima.com/download-center/)
- **Tags:** multi-head, cap, 15-needle
Both heads sew the same design at the same time; you cannot run different designs on each head. Thread breaks on one head are handled with the make-up settings (see Settings below).

### Earlier BAI models (MIRROR-1501, VISION-V22)
- **Type:** Commercial single-head, 15 needles
- **Years:** Earlier models, still supported
- **Manual:** [BAI technical support](https://www.ibaima.com/technical-support/)
- **Tags:** legacy, 15-needle
BAI still lists these model names on its support form. If your machine has the Institch i5 panel, the faults and settings on this page apply. For other BAI-branded machines (for example older "Pro" or multi-head versions) check the panel software name and ask BAI support for the matching manual.

## Error codes
| Code | Message | Meaning | Fix | Models | Source |
|---|---|---|---|---|---|
| Connection Timeout | Connection Timeout | The panel cannot talk to the multi-function (main control) board: loose signal cable, mismatched or damaged board. | Power off, reseat the cable between the panel and the multi-function board, power on. If it stays, the board needs checking or replacing by a technician. | Institch i5 machines | Institch i5 manual (BAI) |
| No Response | No Response | The touchscreen is not responding: loose screen plug or damaged screen. | Power off and reseat the touchscreen plug. If the screen still does not respond, it needs replacing. | Institch i5 machines | Institch i5 manual (BAI) |
| Misalignment | Misalignment (touch) | Touches land in the wrong place on the screen. | Run Screen Calibration from the Settings menu. Replace the screen if calibration does not hold. | Institch i5 machines | Institch i5 manual (BAI) |
| Main axis not in 100° | Main axis not in 100° | The main shaft stopped away from its rest position of 100°, so the machine will not start or move the frame. | Turn the handwheel (or use the panel's main-shaft jog) back to 100°, then restart. If it happens every stop, the servo driver settings or its cables need checking. | Institch i5 machines | Institch i5 manual (BAI) |
| Main axis not turn | Main axis not turn | The main (spindle) motor did not turn: driver parameter error, power to the motor, or a failed driver or motor. Often a jam stops it. | Power off, remove the needle plate and clear any thread or broken needle in the hook, turn the handwheel by hand to check it moves freely, power on. If it still will not turn, call a technician to check the spindle driver and motor power. | Institch i5 machines | Institch i5 manual (BAI) |
| No 0° | No 0° (no zero signal) | The machine cannot read the main shaft's zero position: oil or dust on the zero signal plate, damaged plate or loose cable. | Power off and wipe oil and dust off the zero signal (encoder) plate, then check its cable. Replace the plate if it is damaged. | Institch i5 machines | Institch i5 manual (BAI) |
| Color time out | Color time out | The needle case did not finish a colour change: motor not turning, parts sticking or a loose motor cable. | Clear any birdnest that holds the needles, check the needle case slides freely by hand with power off, then retry. If it still times out, have the colour change motor and cable checked. | Institch i5 machines | Institch i5 manual (BAI) |
| No needle | No needle | The needle position sensor (potentiometer) cannot tell which needle is selected. | Move the needle case to a needle and retry. If the error stays, the needle detection potentiometer needs adjusting or replacing by a technician. | Institch i5 machines | Institch i5 manual (BAI) |
| X motor driver error | X motor driver error | The X motor driver shut down on over-voltage or over-current, or is damaged. | Free any bind in the X travel (hoop against the machine, cap driver catching), then power off and on. Replace the driver if it repeats. | Institch i5 machines | Institch i5 manual (BAI) |
| Y motor driver error | Y motor driver error | The Y motor driver shut down on over-voltage or over-current, or is damaged. | Free any bind in the Y travel, then power off and on. Replace the driver if it repeats. | Institch i5 machines | Institch i5 manual (BAI) |
| Trimmer motor stuck | Trimmer motor stuck | The trimmer did not return home: proximity switch out of place or damaged, loose motor plug, failed motor or board. | Remove the needle plate, clear thread from the knife, and set the trimmer switch back in place by hand. Reseat the motor plug. Replace the switch or motor if it persists. | Institch i5 machines | Institch i5 manual (BAI) |
| Hook motor stuck | Hook motor stuck | The hook-side motor is not moving: loose plug, failed motor or board. | Clear any thread jam in the hook area, reseat the motor plug, power cycle. Call a technician if it continues. | Institch i5 machines | Institch i5 manual (BAI) |
| Broken thread detection error | Broken thread detection error | The thread break sensor (optocoupler board) gives bad readings: board loose or damaged, cable fault, or the top/bottom thread detection settings are wrong. | Check the top and bottom thread detection settings first, then reseat the sensor board and its cable. Replace the board if it still misreads. | Institch i5 machines | Institch i5 manual (BAI) |
| +X limit error | +X limit error | The frame reached the +X travel limit. | Move the frame back the other way, then check the design fits the selected frame and the frame size setting is correct. | Institch i5 machines | Institch i5 manual (BAI) |
| -X limit error | -X limit error | The frame reached the -X travel limit. | Move the frame back the other way and recheck design size, frame setting and start point. | Institch i5 machines | Institch i5 manual (BAI) |
| +Y limit error | +Y limit error | The frame reached the +Y travel limit. | Move the frame back the other way and recheck design size, frame setting and start point. | Institch i5 machines | Institch i5 manual (BAI) |
| -Y limit error | -Y limit error | The frame reached the -Y travel limit. | Move the frame back the other way and recheck design size, frame setting and start point. | Institch i5 machines | Institch i5 manual (BAI) |
| USB not read | USB drive cannot be read | The panel cannot read the stick. | Use a drive under 64 GB formatted FAT32, re-plug it, or try another drive. Do not pull it out until import finishes. | Institch i5 machines | Institch i5 manual (BAI) |
| Memory full | Not enough space for the pattern | Pattern memory is full (about 200 designs or 20 million stitches). | Delete old patterns from the panel, then import again. | Institch i5 machines | Institch i5 manual (BAI) |

## Common problems and fixes
### Upper thread keeps breaking
**Symptoms:** thread, needle, tension
**Likely causes:** needle turned the wrong way or burred, thread missed a guide or tension disc, worn tension spring, needle too small for the thread
1. Rethread the needle that stopped from the cone, pulling the thread into the tension discs so it seats properly.
2. Fit a new needle: the scooped (concave) side faces out, turned about 15° to the right, pushed fully up.
3. Use a 90/14 needle for metallic thread; save small 65/9 or 70/10 needles for fine detail and small lettering.
4. Slow the machine down on dense or small designs.
5. Replace a weak or worn tension spring; BAI notes this fixes uneven stitches and repeat breaks.
**Call a technician if:** one needle still breaks with a new needle and clean path, which points to a burr on the hook or plate, or timing.

### Birdnest under the fabric
**Symptoms:** birdnest, tension, thread
**Likely causes:** upper thread not in the tension discs, upper tension too loose
1. Stop, cut the nest free from underneath, and do not pull the hoop.
2. Rethread that needle all the way from the spool to the needle.
3. Increase the upper tension a little on that needle.
4. Sew BAI's H test file on a flat hoop to check tension balance.
**Call a technician if:** nests continue on every needle after rethreading, which suggests a hook or bobbin case problem.

### Stitches look wrong on one side (tension balance)
**Symptoms:** tension, looping, bobbin
**Likely causes:** upper or bobbin tension out of balance
1. Remember BAI's rule: a problem on the underside points to upper tension; a problem on the top points to bobbin (lower) tension.
2. Adjust the side indicated, a small amount at a time.
3. Sew the H test file and check that about a third of the column width shows bobbin thread underneath.
**Call a technician if:** the bobbin case will not hold a setting.

### Needles break or bend
**Symptoms:** needle, cap
**Likely causes:** needle not fully seated or wrong way round, too small on caps, frame or cap hitting the needle
1. Replace the needle, seated fully up and turned the correct way.
2. On caps, use the Jump stitch type setting (recommended for caps) and a stronger needle.
3. Check the cap is tight on the frame and the driver is locked.
**Call a technician if:** the needle hits the hook or plate, which means timing or needle bar depth is off.

### Machine stops with "Main axis not in 100°"
**Symptoms:** timing, motor
**Likely causes:** the main shaft stopped away from its rest position after a jam or manual turning
1. Clear any thread or broken needle from the hook area with power off.
2. Turn the handwheel (or use the panel jog) until the shaft reads 100°.
3. Restart the design.
**Call a technician if:** it happens at every stop; the spindle servo or its settings need checking.

### Trimmer doesn't cut or leaves long tails
**Symptoms:** trimmer
**Likely causes:** jump stitch trim setting, tail length setting, thread wrapped on the knife, switch out of place
1. Check the Jump Stitch trim setting (default 3) and Length After Trim (default 3).
2. Remove the needle plate and clean thread from the knife area.
3. If you see "Trimmer motor stuck", set the trimmer switch back in place by hand.
**Call a technician if:** the knife is dull or the trimmer motor fails.

### Thread break sensor misses breaks or stops for no reason
**Symptoms:** sensor, thread
**Likely causes:** detection settings too sensitive or turned off, sensor board fault
1. Check Top Thread Broken Test (default 5; a bigger number is less sensitive) and Bottom Thread Inspect (High, Middle or No detection).
2. Make sure neither is set to no detection unless you mean it.
3. If false stops continue, raise the top value one step.
4. If the panel shows "Broken thread detection error", reseat the sensor board cable.
**Call a technician if:** the sensor board needs replacing.

### Frame hits a limit or design is off-centre
**Symptoms:** frame, hoop, registration
**Likely causes:** design larger than the hoop, wrong frame selected, frame size set too big, start point moved
1. Pick the frame that is actually fitted.
2. When adding a custom frame, set its X and Y size about 30 mm smaller than the real frame.
3. Trace the design with the red laser before sewing.
4. After a limit error, move the frame back by hand and re-trace.
**Call a technician if:** the frame hits a limit on a design that traces correctly.

### Cap designs distort or skip
**Symptoms:** cap, registration
**Likely causes:** long stitches on a curved surface, cap loose on the frame, too fast
1. Set Choose Emb Type to Jump for caps.
2. Hoop the cap tightly with the sweatband clipped down.
3. Lower the speed for structured caps and dense fills.
**Call a technician if:** the cap driver moves unevenly or makes noise.

### Design won't load from USB or Wi-Fi
**Symptoms:** file, usb, network
**Likely causes:** wrong format, USB format, full memory, network
1. Save the design as DST or DSB; other formats must be converted first.
2. Use a FAT32 USB stick under 64 GB.
3. Delete old patterns if the panel memory is full.
4. For Wi-Fi, put the computer and machine on the same network and send through cloud.institch.com.
**Call a technician if:** the panel will not read any drive or connect to any network.

### Power cut in the middle of a design
**Symptoms:** power, registration
**Likely causes:** power loss mid-design
1. Restore power; the power-off recovery feature returns to the last stitch.
2. If the frame was moved by hand, use Find The Origin first so the machine knows where the frame is.
3. Back up a few stitches before restarting so the repair overlaps.
**Call a technician if:** the machine will not find the origin.

## Maintenance schedule
| Interval | Task | Notes |
|---|---|---|
| Before first use | Oil the machine | BAI ships a small oil bottle; the machine should be oiled before its first run. |
| Every bobbin change | Brush lint and thread ends out of the hook area | Good shop practice; a short thread end left near the hook catches the new thread. |
| When a needle breaks or shows wear | Replace the needle | The included needles are a general-purpose size. |
| Twice a week (normal daily use) | Oil the machine | Follow BAI's "How to Oil & Maintain THE MIRROR" video for the oil points. |
| Three times a week (more than 8 hours a day) | Oil the machine | Heavier use needs more frequent oiling. |
| As needed | Replace worn tension springs | Restores even thread tension. |
| As needed | Clean the zero signal plate | Oil and dust on it cause the "No 0°" fault. |

## Settings that cause stitch problems
- **Top Thread Broken Test:** default 5. A bigger value is *less* sensitive; "no detection" means the machine keeps sewing after a break.
- **Bottom Thread Inspect:** High, Middle (default) or No detection. Set too high and you get false stops; turned off and empty bobbins go unnoticed.
- **Auto Return Stitches:** default 4. This is how far the machine backs up after a thread break. Raise it if repairs leave gaps.
- **Jump Stitch (trimming):** default 3. Jumps below this count are not trimmed, so a high value leaves more jump threads.
- **Length After Trim:** default 3. Too short and the needle unthreads on the next start; too long leaves tails.
- **Auto Speed Down Stitch:** default 2.0 mm. Stitches longer than this slow the machine.
- **Jump Stitch Speed Down:** default 60% of the current speed during runs of jumps.
- **Auto Jump Stitchs:** default 6.5 mm. Longer jumps are split into shorter moves.
- **Choose Emb Type:** Slow (default) or Jump. BAI recommends Jump for caps.
- **Thick Material Embroidery:** turn on for thick goods to slow the machine down.
- **Needles No.:** must match the machine (15). A wrong value causes colour change trouble.
- **Hole Needle Position:** set to 0 unless you sew eyelets; the needle set here gets special thread break handling.
- **Make Up Method (two-head):** Single (default) means only the head whose thread broke sews the repair; All Heads means both do.
- **Frame setting:** custom frame sizes should be about 30 mm smaller than the real frame. Do not change the frame centre values unless you know why.
- **Reset Frame:** when on, the machine finds the frame origin at every power-on, which helps power-off recovery.
- **Stop Frame Of Moving:** when on, the frame stops at its boundary instead of running into the limit.

## Official manuals, FAQs and support
- [BAI download center](https://www.ibaima.com/download-center/) — THE MIRROR and THE VISION catalogs, the Institch i5 manual, maintenance tips and repair tips (RAR downloads)
- [BAI FAQ](https://www.ibaima.com/faq/) — oiling frequency, needle fitting and sizes, tension test, file formats, Wi-Fi transfer
- [BAI technical support](https://www.ibaima.com/technical-support/) — one-to-one support request form and links to BAI's YouTube channel and Facebook group
- [BAI help center](https://www.ibaima.com/help-center/) — FAQ and blog index
- [BAI service center tutorials](https://service.100horse.com/LearningTutorials/ALL/ALL) — official videos, including threading and "How to Oil & Maintain THE MIRROR"
- [BAI store](https://bai.store/) — product pages, spare parts and warranty

## Frequently asked questions
### What file format does a BAI embroidery machine use?
The Institch i5 panel reads DST and DSB. Convert other formats in your digitizing software first. You can load designs with a FAT32 USB stick under 64 GB or over Wi-Fi through cloud.institch.com.

### How often should I oil my BAI machine?
Oil it before first use, then twice a week for normal daily use, or three times a week if it runs more than 8 hours a day. BAI's maintenance video shows the oil points.

### What does "Main axis not in 100°" mean on a BAI?
The main shaft must rest at 100° before the machine will start or move the frame. Turn the handwheel back to 100°, clear any jam in the hook area, and restart. If it happens at every stop, have the spindle servo checked.

### Which way does the needle go in a BAI machine?
Look at the needle eye: one side is scooped (concave). That side faces out, and the needle is turned about 15° to the right, pushed fully up before tightening.

### Why is my BAI birdnesting?
A nest under the fabric is almost always an upper threading or upper tension problem. Rethread that needle from the spool with the thread in the tension discs and add a little upper tension, then sew the H test file to confirm.

### Can a two-head BAI sew different designs on each head?
No. Both heads of the VISION-2 sew the same design at the same time. BAI suggests a two-head for runs over about 20 pieces, and two single-heads if you mostly do short, mixed jobs.

### Does BAI publish numbered error codes?
No numbered code list is public. The Institch i5 manual lists named panel faults (such as Color time out, No 0° and the X/Y limit errors) with causes and fixes, which are summarized above. For anything else, use BAI's free one-to-one technical support.

## Diagrams

- [Five-minute diagnosis](https://easydigitizer.com/troubleshooter/img/diagnose-flow.svg): Where to start when the machine stops or sews badly.
- [Upper thread path](https://easydigitizer.com/troubleshooter/img/thread-path.svg): Every guide from the cone to the needle eye — the fix for most breaks and nests.
- [Why birdnests happen](https://easydigitizer.com/troubleshooter/img/birdnest.svg): What a nest is, the usual causes in order, and how to clear one safely.
- [The I-test for tension](https://easydigitizer.com/troubleshooter/img/tension-test.svg): Read the back of a satin column to balance top and bobbin tension.
- [Bobbin drop test](https://easydigitizer.com/troubleshooter/img/bobbin-drop-test.svg): Set bobbin tension before you touch the top tension.
- [Needle orientation](https://easydigitizer.com/troubleshooter/img/needle-orientation.svg): Long groove to the front, scarf to the hook, pushed fully up.
- [Hook timing](https://easydigitizer.com/troubleshooter/img/hook-timing.svg): What correct hook-to-needle timing and clearance look like.
- [Presser foot height](https://easydigitizer.com/troubleshooter/img/presser-foot-height.svg): Too high causes flagging and loops; too low drags and breaks thread.
- [Hooping layers](https://easydigitizer.com/troubleshooter/img/hooping.svg): Firm, flat and square — the root of most puckering and registration faults.
- [Caps: frame and sequence](https://easydigitizer.com/troubleshooter/img/cap-frame.svg): Cap frame set-up, centre-out sewing and safe sew height.
- [Cleaning and oiling points](https://easydigitizer.com/troubleshooter/img/maintenance-points.svg): Daily and weekly care points on a multi-needle head.

---

Part of the EasyDigitizer embroidery machine troubleshooter: https://easydigitizer.com/troubleshooter/ · Agent playbook: https://easydigitizer.com/troubleshooter/agent.md · Not affiliated with any machine maker; the machine's own manual takes priority. Design-related sew-out problems (density, underlay, pull compensation): https://easydigitizer.com/help