‘CHMSL’ Is Possibly The Most Confounding GM Acronym Ever14
One comes to learn a thing or two after years of obsessively covering General Motors on the daily. One of those things is that the automaker has a penchant for acronyms such as GMNA, GCCX, GME, GMSA, GMI, GMF, VLE, O1SL, CCA, AFL, SIDI… the list of GM acronyms goes on and on. It would seem that The General wants to have an abbreviation for everything, including its own name (GM). But the most confounding one we have to come across yet is CHMSL.
If you don’t know what CHMSL stands for, open the below toggle to find out what it’s all about. And if you already know what CHMSL is all about, congrats… though you still might want to open the toggle below for some interesting info about the feature.
CHMSL = Center High Mounted Stop Light (or Lamp, if you so prefer).
A GM lighting technology, the Center High Mounted Stop Lamp is the horizontal stop light that typically sits at or near the top of a vehicle, and helps following vehicles better see a vehicle that’s applying its brakes and slowing. It’s more colloquially known as the third brake light.
CHMSL is an industry term and is not limited to GM. It has officially been around since 1986 in passenger cars and 1994 in light trucks. In fact, According to the National Highway Traffic Safety Administration (NHTSA), the implementation of CHMSL has helped reduce rear crashes by about 4.3 percent annually. The feature is standard on all current General Motors vehicles, with the exception of Cutaway Vans and Chassis Cab pickup trucks, which are sold as incomplete vehicles.
Most recently, GM has even found a way to take CHMSL beyond function of better visibility. In the Cadillac ATS and CTS families, for instance, CHMSL is placed on the rear deck-lid in such a way that not only serves its intended purpose as the third brake light, but also serves as a functional spoiler of sorts that provides downforce, thereby improving aerodynamic performance.
So there you have it: CHMSL – probably the most amusing GM acronym to date. Have any other GM acronyms to share? Sound off in the comments section.
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Center high mounted stop lsmp
Uhh, this one isn’t confusing at all…never has been. This is what I refer to the light as almost all the time.
I believe ever since this light became mandatory on vehicles it is what’s it’s referred to industry and regulatory wide
I remember back in the mid 80’s I was working at “Minute Lube” in Flagstaff, AZ. when a guy came in with this funny looking (tail light?) in the back window of the sedan (remember those). He said he/they were pitching it to the NHTSA to make them mandatory equipment in an effort to reduce rear end collisions, remember the Ford Pinto.
Can’t remember if he or the car was the same one that came in for service with whistlers on the front of the car. Said to scare wildlife off from an approaching car in mountainous areas.
Though they were already around before that, dunno what he was “pitching” but GM had them on the
1971-1978 Toronados, they were even better since there were 2 of them one on each side of the car and they also repeated the turn signals too from what I recall.
And those whistlers have been around for years.
dunno what he was “pitching”?
= Federal Mandate = on paten = profit from paten.
The ones on the Toronado were probably more about letting the drivers on either side know what the driver of the Olds was doing. Since the taillights were pretty far back and were blocked from the sides by those long ass quarter panels sticking out past them. From far enough back you might not even be able to differentiate them from the lower taillights.
The center (break light only) by being an additional light and being far from and higher then the taillights. Was (pitched) to be better at getting your attention when the car in front of you applied the breaks. Which was what the federal mandate was about. They are even higher now being above the rear window. Did GM even patent the one on the Toronado?
It was no mystery to anyone around 84-85 that saw this acronym is most every magazine story published. They had little else to talk about with the lack of HP and FWD.
I remember they were like the LED DRLs of the day as people even paid to add them to the older cars to look like they were on the new trend.
Center High Mounted Stop Lamp……..then again, I know the difference between a CTS and and ATS and an CT6, which puts and I can use CUE without issues…….me in the top one percentile of the human population……
Slow news day?
I just call it the “third brake light”. It was a given that a car would already have 2, so adding one more by mandate would make a total of 3.
Don’t forget the old “PRNDL” lever.
Very interesting story. BTW these are abbreviations and not acronyms. Acronyms are pronounced as a word like NASA.
Most people pronounce it as one: “Chim-sul”.
ITS FINE BY ME AS LONG AS I KNOW WHAT IT IS