JLL treadmill error codes

Written by Jamie Miller, Founder & EditorLast checked 18 September 2026

We are not publishing a JLL error code table, because we do not have one from a source we would stand behind. Code meanings differ between models and between firmware versions on the same model, and a list assembled from forum posts would look authoritative and be wrong for some readers. What follows is what to do instead, which works whatever the code says.

Why not just publish a list

Plenty of pages will tell you E01 means one thing and E02 another. Some of those are right for some machines. The problem is that you cannot tell which, and the consequence of a wrong answer here is not an inconvenience: it is somebody deciding a motor fault is a sensor fault and carrying on using the machine. We would rather send you to the one source that is definitely right for your model.

Do this instead

Write the code down exactly as shown, including whether it is E01 or E1, and note what the machine was doing when it appeared.
Try a full reset. Unplug at the wall for a minute, reseat the safety key. The full sequence. A code that clears and does not return was transient. One that returns immediately is reporting something real.
Check your manual. JLL publish manuals for their machines, and the code table for your exact model is in it. That table beats any website, including this one.
Contact JLL directly with the model, the code and what the machine does. They hold the definitive list and the firmware history.
Stop using it if the code is accompanied by a burning smell, a tripping breaker, or a belt that moves when it should not.

What a code will not tell you

Codes report a symptom the control board can detect, not a diagnosis. A speed sensor code can be caused by a dirty sensor, a loose connector, a failing board, or a belt so tight the motor cannot reach the speed it was asked for. The same code, four repairs.How to describe the fault so an engineer can act on it.

Worth ruling out first

Before assuming electronics: a dry deck makes the motor work harder and can trigger speed-related codes. Lubrication andbelt tension are cheap to check and rule out.

What we have not established

We do not hold JLL's error code table, we have not verified any circulating version of it, and we have tested no JLL machine. We also could not source a current JLL product with checkable specifications: the S300 and T350 no longer appear in JLL's own UK range.How we review.