F1 Rear Light

[fizz876]

What is the rear flashing light on an F1 car for and what does it mean?

[Westy Pre-Lit]

Used when there is bad visibility.

[Paulle]

I thought it was traction contol?

[Graebob]

or when pit lane speed limiter is active

[Munter]

doesn't it also come on when the traction control kicks in? Or is my memory playing tricks on me...

[Graebob]

FIA Regulations said:

14.5 Rear light:
All cars must have a red light in working order throughout the Event which:
- has been supplied by an FIA designated manufacturer;
- faces rearwards at 90° to the car centre line and the reference plane;
- is clearly visible from the rear;
- is mounted nominally on the car centre line;
- is mounted 300mm (+/-5mm) above the reference plane;
- is no less than 595mm behind the rear wheel centre line measured parallel to the reference plane;
- can be switched on by the driver when seated normally in the car.
The two measurements above will be taken to the centre of the rear face of the light unit.

FIA Regulations said:

All cars must have a red light on the rear of the car in a specific location defined by the FIA regulations. The driver must be able to switch this light on at any time. This is usually done in poor weather conditions in order to make the car more visible to following drivers.

I can't find anything about whether the light is active during pit stops or when traction control is working.

Edited by Graebob on Sunday 22 July 14:37

[Paulle]

So it's not like rear fog lights when the driver switches it on in September & it stays on 'til the MOT

[madazrx7]

I thought it showed that either the pit speed limiter was on or the car had wets on?

[paolow]

maybe i can clarify - a bit - i think

The cars have had to have a red light for yonks.
but.
back when benetton were cheating there was the suggestion that some teams were using the pit lane speed limiter (which worked on rear wheel speed and ignition cut) as a rudimentary launch control to get off the grid quicker. quite clever i thought and difficult to prove as the software and sensors had to be there anyway.

so

The FIA said - when the pit lane limiter is in use the rear light must flash to make clear to all and sundry that you are either a) cheating at the start or b) in the pit lane.

now traction control is allowed the rules have gone a bit funny and it still has to flash on a pit limiter but not when TC works but it does in inclement conditions - bit like a rear fog

IIRC

[Eric Mc]

I think red lights were originally introduced in the 1970s.

[TonyHetherington]

I recall that Benetton accusation! As you said, it was suggested that they were using the Pit Limiter as a way of launch control (or traction control in some corners) as the sensors and software had to be there, so the light flashing (and now the fuel cap having to be up) must occur when the pit lame limiter is on.