My Carrera E-Bike Has Stopped Working — How to Diagnose the Fault
Is your Carrera or Raleigh Array e-bike cutting out, losing pedal assist, or failing to provide power? This guide will help you identify the fault yourself and show you how to fix it without an expensive main dealer repair bill.
These are the most common complaints from Carrera owners, and in the majority of cases the fault is simpler and cheaper to fix than you might think. In the majority of cases, the fault is a failed torque sensor, a small, inexpensive component that most owners can replace at home in under an hour.
Step 1: Check the battery
Make sure the battery is fully charged and properly clicked into its housing. A partially seated battery can cause intermittent power loss or a complete failure to start. Remove it, refit it firmly, and try again before doing anything else.
Step 2: Check that pedal assist is switched on
Carrera e-bikes using the SR Suntour HESC system will not provide motor assistance unless pedal assist is actively enabled on the display. Check that the display is on and that the assist level is set above zero.
Step 3: Check for an error code on the display
If your display is showing a code beginning with E, such as E21, E22, E00, or E32, the system has already identified the fault for you. Each code points to a specific component.
E21 and E22 are by far the most common codes on Carrera and Raleigh e-bikes and both point to the torque sensor. If you have one of these codes, read our full error codes guide and our torque sensor fix guide for the next steps.
Step 4: No error code but still no power
The bike powers on, the display looks normal, there is no error code, but the motor does not respond when you pedal.
The HESC system does not always show an error code when the torque sensor fails. If the sensor degrades gradually rather than failing suddenly, the controller may not detect a fault to report. It simply receives no signal and provides no assistance.
The torque sensor is still the most likely cause. It is the most failure-prone component in the HESC system and accounts for the majority of no-assist faults, with or without an error code.
Step 5: Identify whether it is the torque sensor, the motor, or the controller
Observe when and how the fault occurs.
The motor turns on briefly then stops. The sensor is likely sending an intermittent signal. This points to a torque sensor fault.
The motor never activates at all. The sensor may have failed completely, or there is a wiring fault between the sensor and the controller. Check the connector at the sensor first.
The motor works when you set off but cuts out under load. This is a common sign of a failing torque sensor. The internal mechanism degrades and struggles to read force correctly when pedal pressure increases.
The motor works but power or speed feels reduced. This is unlikely to be the sensor. Check the assist mode level on the display.
The display is blank or showing persistent errors. This may point to the display unit itself or a controller communication fault.
The torque sensor is the cause in the large majority of cases where the motor stops responding to pedalling. Motor and controller failures do occur but are far less common.
Step 6: Check all connectors before ordering a replacement
Before replacing the torque sensor, disconnect and reconnect the sensor connector at the bottom bracket. Road grit and moisture can cause corrosion that interrupts the signal. A clean reconnect sometimes resolves the fault without any parts needed.
On earlier Carrera models, the motor connector near the rear wheel is also known to work loose over time due to cable tension. If the torque sensor connector looks clean and secure, check this connector as well before drawing any conclusions.
If the fault persists after checking both connectors, replace the torque sensor.
Step 7: Choose the correct replacement sensor
Carrera e-bikes use one of two sensor types, 4-pin or 6-pin. They are not interchangeable and ordering the wrong one will not work on your bike.
4-pin sensor covers the Crossfire-e, Vulcan-e, Vengeance E, and Subway E on pre-2021 models.
6-pin sensor covers the same models from 2021 onwards.
To confirm which you need, look at the connector on the existing sensor. Four wires means 4-pin. Six wires means 6-pin.
The same sensors are also compatible with selected other Raleigh models using the SR Suntour HESC drivetrain. If you are unsure whether your Raleigh model is compatible, contact us before ordering.
View the 4-pin torque sensor - £39.99
View the 6-pin torque sensor - £44.99
What about the Halfords repair quote?
Several of our customers have come to us after being quoted £150 or more at Halfords for what turned out to be a torque sensor replacement. The part costs £39.99 or £44.99, and most owners fit it themselves at home in under an hour. You will need a crank extractor, an adjustable spanner, and a screwdriver. If you are not confident fitting it yourself, any independent bike shop can carry out the replacement for considerably less than a main dealer would charge.
Get in touch if you are still unsure
If you have worked through these steps and are still not sure what the fault is, contact us. We have fulfilled over 1,000 orders for Carrera and Raleigh owners and can help you identify the correct part from a description of the symptoms.