Purion display turns off after a few pedal revolutions

[Master Link]

Hi,
My friend has a Trek Powerfly 5 with the Bosch CX4 motor. When the bike is turned on the Purion display activates and stays on. Once he starts to pedal the display turns off after a few pedal revolutions. Before it turns off the speed can be seen, so it must be receiving wheel data.

Anyone have any ideas what this can be?

 

[FrostFlame]

It could be a few things causing this glitch. One possibility is a loose connection somewhere in the wiring harness, especially around the motor or the display unit itself. Another thing to check is the battery level and connections; if it's not securely attached or if it's running low, it might cause the display to act wonky. If those don't seem to be the issue, it might be worth taking it to a bike shop that specializes in e-bikes or reaching out to Trek's customer support for some troubleshooting tips.

 

[Stihldog]

The Yorkshire Mechanic (Dave) just put out a YouTube vid on this issue.

Might help diagnose the problem before you take it to the LBS. Hopefully it’s not the motor.

 

[Master Link]

It could be a few things causing this glitch. One possibility is a loose connection somewhere in the wiring harness, especially around the motor or the display unit itself. Another thing to check is the battery level and connections; if it's not securely attached or if it's running low, it might cause the display to act wonky. If those don't seem to be the issue, it might be worth taking it to a bike shop that specializes in e-bikes or reaching out to Trek's customer support for some troubleshooting tips.

Thanks, I’ll tell him.

 

[Master Link]

The Yorkshire Mechanic (Dave) just put out a YouTube vid on this issue.

Might help diagnose the problem before you take it to the LBS. Hopefully it’s not the motor.

Thanks, I’ll have a look.

 

[Miket775]

Had the same issue as per the video - my bike shop sent my my motor away (think it was to @Bearing Man) who luckily were able to fix the board which fixed it

 

[Master Link]

Had the same issue as per the video - my bike shop sent my my motor away (think it was to @Bearing Man) who luckily were able to fix the board which fixed it

Thanks, I’ll tell him.

 

[Master Link]

Update: the motor was sent back to the company that replaced the bearings and they have repaired it FOC.