Hey there, e-bike riders! Getting an error code on your display is super frustrating, especially when your pedal assist just quits on you.

If you ride a dual-motor bike like a Keteles and you’ve seen the dreaded Error Code 03 pop up, particularly right after a tricky pedal or crank removal, you’re not alone. Let’s dive into why this happens and how you can get back to riding, without hitting your bike with a hammer!

Recommended: Are Electric Bikes Available for Purchase on Temu?

🛑 Step 1: Understanding “Error 03” – What Is It Really Telling You?

First, let’s clear up the confusion about this code. E-bike errors can mean different things depending on the brand, but for most systems, Error 03 points to two main issues:

A. The Most Common Culprit: Motor Hall Sensor Error

In the majority of e-bikes, Error 03 signals an Abnormal Hall Signal from the Motor.

The Hall sensors tell the controller how fast and in what position the motor is spinning. If this signal gets messed up, the controller can’t deliver power, and your pedal assist dies.

  • The #1 Cause? A loose or damaged motor cable connection.

B. The Second Possibility: Pedal Assist Sensor (PAS) Failure

For some brands, including yours, Error 03 can directly mean a Pedal Assist Sensor (PAS) Issue.

The PAS sensor is what detects your pedaling motion. If it fails, the bike thinks you aren’t pedaling, so it cuts the power.

  • Why You Should Suspect This: If the error appeared immediately after you violently removed your left pedal/crank, the PAS sensor is a prime suspect!

Recommended: Costco Electric Bike Review 2025 | Best E-Bike Models, Prices & Buying Guide

🛠️ Step 2: Troubleshooting – Start Simple, Check Everything!

Before you buy new parts, let’s run through the quick and easy checks.

1. Check the Motor Connector (The Easiest Fix)

Since a loose motor cable causes 90% of Error 03 problems, this is your first stop!

  • Where to Look: Follow the thick wire coming out of your rear (or front) wheel motor. It should lead to a large, round, waterproof connector somewhere near the chainstay or under the battery tray.
  • The Fix:
    1. Turn off your bike and remove the battery.
    2. Carefully unplug the motor connector. Check the internal pins to make sure none are bent, dirty, or corroded.
    3. Plug it back in firmly. Make sure the arrows (or alignment notches) are perfectly lined up and that the connection feels totally secure.
  • Result: Turn the bike on. Did Error 03 disappear? Great! You’re done.
E-bike motor cable waterproof connector unplugged for inspection.
Close-up view of the e-bike motor cable connection point. Check here for loose pins or corrosion, a common fix for Error 03.

2. Inspect the PAS Sensor Connection

This is crucial, especially since you were messing with the pedal area.

  • Where to Look: Follow the cable coming out of your bottom bracket area (where the cranks meet the bike frame).
  • The Fix:
    1. Locate the PAS sensor cable connector.
    2. Unplug and replug it to ensure a solid connection. Check the wires for any obvious cuts or pinching along the frame.

Recommended: Best Electric Bikes for Seniors 2025: Complete Safety & Comfort Guide

🔨 Step 3: Dealing with Physical Damage (Did You Break It?)

If the simple connection checks didn’t work, it’s time to face the music about the pedal removal.

The Dangers of Hitting the Crank

You mentioned you had to “hammer it off the back side.” This kind of force is dangerous if your bike uses an integrated PAS sensor.

Many modern e-bikes have the sensor and magnetic ring housed inside the bottom bracket assembly (the “crank tube”). Smashing the crank to get it off can cause:

  • Sensor Shattering: The impact can crack or break the plastic sensor housing inside the tube.
  • Magnet Disc Damage: The magnetic ring that the sensor reads might be knocked out of position or damaged.

💡 What Should I Have Done?

You correctly noted that the pedal/crank had a structure for a puller tool.

  • The Correct Way: Never use a hammer to remove a crank arm! You need a specialized crank puller tool to gently and safely thread into the crank and push it off the spindle.
  • Lesson Learned: Using the correct tool prevents internal parts, like your PAS sensor, from taking the full shock of your removal attempt.
Mechanic using a crank puller tool to safely remove a bicycle crank arm from the bottom bracket.
The Correct Way: Always use a specialized crank puller tool to prevent damaging the internal pedal assist sensor during crank removal.

❓ What’s the Final Verdict?

If you’ve checked the motor cable and the PAS connector, and Error 03 is still there, here’s your final diagnostic:

Scenario Diagnosis Next Step
Error 03 persists, and your bike uses Hub Motors. Motor Hall Sensor or Controller Failure. Likely a faulty motor or controller. Use a multimeter to test the Hall wires, or take it to a professional for advanced diagnostics.
Error 03 persists, and it started immediately after the hammer incident. PAS Sensor is Physically Damaged. The sensor is likely broken. You will need to replace the integrated PAS sensor in your bottom bracket. This usually requires removing the crank, which you should now do with the proper tool!

Bottom Line: While Error 03 often points to the motor, the timing of your failure-right after a violent crank removal-makes the PAS sensor damage the most likely culprit. Get that crank puller tool and prepare to replace the sensor!

Safe riding!