Horizon, Vision and Matrix (Johnson Health Tech) Error Codes

Horizon publishes its treadmill error guidance as separate help-centre articles rather than one table: E1 and E2 each have their own troubleshooting document, the motor control board has a blink-code table, and a code at power-on can simply mean a stuck key.

Before you use this table: Horizon, Vision and Matrix are all Johnson Health Tech. The home-treadmill codes below are Horizon's; Matrix commercial treadmills use a different, longer code set where E1, E2 and E3 are incline faults, not belt faults. Check which family you have before acting on a code.

Leading zeros, dashes and spacing do not matter: E01, E-1 and E1 find the same row.

Manufacturer-documented Meaning taken from a manufacturer manual or support page.   Reported Consistent owner and technician reports; the manufacturer has not published this code. Confirm with them if it matters.

CodeWhat it meansWhere to look first
E1Also shown as: E01Horizon home treadmills (T101, T202, 7.0 AT, 7.4 AT, Elite and earlier models)Manufacturer-documented

Horizon files E1 under "E1 error message and/or no treadmill belt movement": the controller did not see the belt move when it should have.

Likely causes

  • Belt cannot move: dry deck, over-tight belt, or a heavy load at start
  • Speed sensor (reed switch) out of alignment or its magnet missing
  • Loose connections at the motor control board, often after a move

Source checked 2026-09-13

  1. Confirm the safety key is fully in and try a normal start with nobody on the belt
  2. Check deck lubrication and belt tension against the manual
  3. If it started working after a move or reassembly, reseat the console cable and the connections you can reach with the power off

Treadmill Turns On but Belt Won’t Move? Diagnose It Before Replacing Parts →

Also relevant

E2Also shown as: E02Horizon home treadmillsManufacturer-documented

Horizon files E2 under "E2 error message and/or erratic speed": the belt speed is not tracking what the console asked for.

Likely causes

  • Speed sensor giving an unstable signal
  • Friction from a dry deck or tight belt
  • Power supply through an extension lead or shared circuit
  • Electromagnetic interference near the console

Source checked 2026-09-13

  1. Plug the treadmill directly into a wall outlet
  2. Lubricate and re-tension the belt if due
  3. Keep phones and other devices off the console tray while you test

Treadmill Speed Keeps Changing? Why It Surges, Slows Down or Speeds Up →

Safety key offAlso shown as: SAFETY KEY OFF, KEY OFFHorizon treadmillsManufacturer-documented

The console cannot see the safety key. Horizon treats a display of dashes or all 8's the same way.

Likely causes

  • Key not seated
  • Key magnet weak or damaged
  • Console switch fault

Source checked 2026-09-13

  1. Remove and refit the key squarely
  2. Follow Horizon's safety key reset article
  3. If the message persists with a good key, the console switch needs service

Treadmill Turns On but Belt Won’t Move? Diagnose It Before Replacing Parts →

Dashes or 8'sAlso shown as: -----, 8888Horizon treadmillsManufacturer-documented

A display of only dashes or 8's is Horizon's safety-key state, not a hardware fault.

Likely causes

  • Safety key removed or not detected

Source checked 2026-09-13

  1. Refit the safety key and run the reset in Horizon's article

Treadmill Turns On but Belt Won’t Move? Diagnose It Before Replacing Parts →

Error at power-onAlso shown as: STARTUP ERROR, STUCK KEYHorizon treadmillsManufacturer-documented

Horizon says an error code shown as soon as the treadmill is switched on can mean a key on the console is stuck down.

Likely causes

  • A console button held down by the overlay or by debris
  • Liquid under the keypad

Source checked 2026-09-13

  1. Press each console key a few times and check none stays depressed
  2. Clean the keypad; if a key remains stuck the overlay or keypad needs replacing

Treadmill Troubleshooting: Diagnose Common Problems by Symptom →

MCB LED 2 blinksAlso shown as: 2 BLINKS, MCB 2Horizon treadmills with a digital motor control boardReported

The controller's status LED signals an optical encoder (speed feedback) problem. Horizon publishes the blink table as an image; this row follows BarBend's transcription of it.

Likely causes

  • Encoder or speed sensor not reporting

Source checked 2026-09-13

  1. Seeing the LED means removing the motor cover: leave it to a technician unless your manual describes it
  2. Treat as a speed-signal fault: sensor, magnet and wiring

Treadmill Turns On but Belt Won’t Move? Diagnose It Before Replacing Parts →

MCB LED 3 blinksAlso shown as: 3 BLINKS, MCB 3Horizon treadmills with a digital motor control boardReported

Motor current overload: the controller measured more current than it allows.

Likely causes

  • Dry deck or tight belt
  • Motor wearing out

Source checked 2026-09-13

  1. Lubricate and re-tension the belt
  2. If it repeats, have the motor's current draw measured

Stop: Repeated overloads heat the motor and controller.

Treadmill Belt Stops When You Step On It? Find the Cause Before Tightening Anything →

Also relevant

MCB LED 4 blinksAlso shown as: 4 BLINKS, MCB 4Horizon treadmills with a digital motor control boardReported

Motor damaged or driven too hard.

Likely causes

  • Motor fault
  • Sustained overload

Source checked 2026-09-13

  1. Stop using the treadmill and arrange service

Stop: Do not keep resetting a controller that reports motor damage.

Treadmill Troubleshooting: Diagnose Common Problems by Symptom →

MCB LED 5 blinksAlso shown as: 5 BLINKS, MCB 5Horizon treadmills with a digital motor control boardReported

Safety key not detected by the controller.

Likely causes

  • Key not seated
  • Console-to-controller connection

Source checked 2026-09-13

  1. Refit the safety key; reseat the console cable with the power off

Treadmill Turns On but Belt Won’t Move? Diagnose It Before Replacing Parts →

MCB LED 6 blinksAlso shown as: 6 BLINKS, MCB 6Horizon treadmills with a digital motor control boardReported

Incline motor stuck or damaged.

Likely causes

  • Incline motor stalled at a limit
  • Motor or its wiring

Source checked 2026-09-13

  1. Run the incline calibration from your manual
  2. If the deck is jammed, do not force it

Treadmill Incline Not Working? How to Tell Calibration, Wiring and Motor Faults Apart →

MCB LED 7 blinksAlso shown as: 7 BLINKS, MCB 7Horizon treadmills with a digital motor control boardReported

Console and motor control board are not communicating.

Likely causes

  • Console cable unplugged or pinched
  • Board fault

Source checked 2026-09-13

  1. Reseat the console cable at both ends with the power off

Treadmill Troubleshooting: Diagnose Common Problems by Symptom →

MCB LED 8 blinksAlso shown as: 8 BLINKS, MCB 8Horizon treadmills with a digital motor control boardReported

Incline motor and motor control board are not connected.

Likely causes

  • Incline motor plug loose at the board

Source checked 2026-09-13

  1. With the power off, check the incline motor connector at the controller

Treadmill Incline Not Working? How to Tell Calibration, Wiring and Motor Faults Apart →

E1 (Matrix T5x)Also shown as: MATRIX E1Matrix T5x commercial treadmill (DGC5X console)Reported

On the Matrix T5x, E1 is an incline fault: the elevation potentiometer reads in reverse. It is not the belt-movement E1 of Horizon home models.

Likely causes

  • Incline motor or potentiometer wiring reversed or faulty

Source checked 2026-09-13

  1. This is service documentation for a commercial machine: log the code and call the service provider

Treadmill Incline Not Working? How to Tell Calibration, Wiring and Motor Faults Apart →

E2 (Matrix T5x)Also shown as: MATRIX E2Matrix T5x commercial treadmillReported

Elevation out of range.

Likely causes

  • Incline position feedback outside limits

Source checked 2026-09-13

  1. Service call; calibration and incline motor checks are technician procedures on this machine

Treadmill Incline Not Working? How to Tell Calibration, Wiring and Motor Faults Apart →

E3 (Matrix T5x)Also shown as: MATRIX E3Matrix T5x commercial treadmillReported

Elevation stall: the incline was told to move and did not.

Likely causes

  • Incline motor, wiring or mechanical jam

Source checked 2026-09-13

  1. Do not force the deck; service call

Treadmill Incline Not Working? How to Tell Calibration, Wiring and Motor Faults Apart →

Code not listed? Not every brand publishes its codes, and we only list meanings we can trace. Two things help:

Sources and when they were checked