Brake Light Brightness Problem

[rudholm]

While driving to the Truck Unveil event last month I noticed something odd with my brake lights. They work correctly under regen braking, but if there's no regen braking going on and I just have my foot on the brake pedal to hold the car still, the brake lights come on at about half brightness. Sometimes, after several seconds, they'll jump to full brightness. It seems like a weird failure mode. Has anyone had this happen?

 

[DeedWest]

My first Roadster had that issue, and it was a 2011 2.5. It was extremely intermittent but was never actually diagnosed by the service center. It now has a new owner and I have not heard of any complaints from him.

Could be a wiring issue in the tail lamp assembly, but I'm not an expert. Let us know if you find out anything!

 

[Rotarypower]

Any update? Could be the brake light switch, or if wired thru a relay, perhaps the relay. Would be nice to have a wiring diagram of the brake light circuit. But seeing as we can’t get that info unless you live in Mass., perhaps it is no different from the Lotus Elise diagram. May want to research similar issues on the Lotus forums?

 

[ecarfan]

I noticed something odd with my brake lights. They work correctly under regen braking, but if there's no regen braking going on and I just have my foot on the brake pedal to hold the car still, the brake lights come on at about half brightness.

how could you tell this while driving?

 

[Fiddler]

Any update? Could be the brake light switch, ...

The brake pedal switch can easily fail if the pedal puts too much force on the switch. The brake pedal switch is a double pole, single throw switch with one pole normally closed and the other pole normally open. Plus 12V is wired to both poles and the switch connects one circuit to the 12V and disconnects the other circuit from the 12V when the brake pedal is pressed.

. +12VDC from fuse

 

[X.l.r.8]

Why is this information only available if you live in Mass.? Am I missing something?

 

[backmost]

I have the service manual if anyone is interested just PM me

 

[gregd]

Why is this information only available if you live in Mass.? Am I missing something?

I believe its a result of a "right to repair" law in that state.

 

[X.l.r.8]

Ohhh, gotcha.

 

[Fiddler]

I believe its a result of a "right to repair" law in that state.

Sadly gregd is correct. Only people living in Mass. have the "right to repair" law. The dealers hate "right to repair" and influence the legislation accordingly. The USA has the best politicians money can buy.