Lighting Issues

[AOJAMES]

My wife got me the upgraded headlight for my Expand 5 Plus for Xmas. Installed with no issues, simple plug and play. Here we are a few days later and I turn on the bike and the headlight was dim and the tail light is not working. If I unplug the light the tail light comes back. With the original light there are no issues. Also worth mentioning that this seems to be intermittent. The other day I lowered my screen brightness and the light came on full power with now issue. I plugged the bike in to charge and when I turned the bike back on the issue stated again. Bike is only 3 months old. Any ideas?

[John Rose]

Is that the "Premium Headlight"? https://radpowerbikes.ca/collections/accessories/products/premium-rad-headlight-2020
It sez:

Compatibility
All Rad ebike models except:
RadExpand 5 Plus
Radster Road
Radster Trail
RadWagon 5
Rad ebike models produced before 2018.

They do not say if it's due to any mechanical mounting conflicts, or the electronics.

[AOJAMES]

Correct. It's listed as working with the RadExpand 5 Plus which is what I have.

[John Rose]

Correct. It's listed as working with the RadExpand 5 Plus which is what I have.

Uh . . . What?
The word except means that it is not compatible with the RadExpand 5 Plus (for whatever reason).

[SemperVee]

 YOU might need to install a diode for it to work.  I had to do that on my Moto Guzzi Motorcycle when I installed an additional flashing brake light that would not work correctly when the brake was actuated.  You have something along the same lines.  You are introducing a new flow to the electronics with a non standard light.