GSTOP Brake Light Flasher : braky-braky, blinky-blinky

 

TL;DR it's easy to have the brake lights flash for extra safety 

GSTOP® Emergency Brake Light Display, quite a mounthful for a miniature flasher module that weighs only 9 grams.

It works a treat and adds some sense of safety when braking hard, the extra visibility it provides is a welcome addition.

How does it work ?  When brakes are applied, it quickly wakes up and starts measuring the G-load with its built-in accelerometer. At first your brake lights are lit just as usual. But as soon as 0.6g of deceleration is reached, it flashes with a 2Hz frequency.  If 0.8g is reached, it flashes with a 3Hz frequency.  The blinking is maintained for 2 seconds after the full stop of the vehicle.

The power side is "just" the NC (normally closed) side of a relay, meaning that its failure mode is that your brake lights will just work as usual if the unit is defective.

I've installed it under the pedal box cover with the provided 3M double-sided tape.

On the brake pedal switch you will find 2 wires : a green one that provides the "accessory" +12V, and the green+purple stripe one that goes to the brake lights. 

WARNING : the flashing unit is rated for 2A max.
Better safe than sorry and check your car before installing that module. The test is easy and consists in pushing one lead of your multimeter in each spade of the pedal switch (in ampmeter mode). The current will bypass the pedal and flow through the multimeter, giving you your current reading. If you are above the rated 2A, it might be best to install the GSTOP on the 3rd brake light rather than at the pedal switch.
We are safe with the Caterham 170 and its new type of LED rear units, as I've measured only 0.4A total to power the 3 brake lights.

The GSTOP is inserted between the output of the pedal switch and the green+purple wire. It's as easy as it sounds : just install a pair of flat spade connectors, one male, one female on the red wires of the GSTOP (no polarity to worry about).

I got my ground by pushing a good length of the bare wire of the black lead to a riv-nut for the pedal box cover.

The long edge on the opposite side of the connector has to face forward. I was happy for the picture once the adhesive was applied to the module and the label wan not visible anymore, good job GSTOP people, good job.

Testing is easy enough as you can let it hang with the "this way forward" side to the ground, so it enjoys that good organic "earthy" 1 g continuous acceleration that keep us all firmly on the ground. Turn the ignition key, put your foot on the pedal, and let it blink.

Included in the box is a test wiring loom equipped with a LED and a 9V battery connector. I would advise on testing that the unit is fully functional before messing with the car.

The sticker was placed on the side wall of the pedal box. Which is way more compact on LHD cars than on RHD ones.

A few weeks later :
I've since thought about the opportunity of installing a miniature 12V buzzer across the red wires, and it would work like this :

• No brakes : no power, no nothing.
• Brakes and no flashing : the red wires are shorted by the relay and no current will flow through the buzzer
• Brakes and flashing : the relay is open and current flows through the buzzer to the brake lights, but the current would be so low that the lights should be considered as a grounding for the buzzer, I don't expect them to emit any light.  >> To be tested ASAP

 Video below : GSTOP in action.