GM Volt Forum banner
1 - 11 of 11 Posts

·
Registered
Joined
·
2 Posts
Discussion Starter · #1 ·
My Forward Automatic Braking on my 2017 Volt does not work. It doesn't seem to have ever worked. The dealer says they check it and never find anything wrong. I even had a message popup that said Forward Automatic Braking unavailable.

Not sure what to do. Any suggestions?
 

·
Registered
Joined
·
5,410 Posts
My Forward Automatic Braking on my 2017 Volt does not work. It doesn't seem to have ever worked. The dealer says they check it and never find anything wrong. I even had a message popup that said Forward Automatic Braking unavailable.

Not sure what to do. Any suggestions?
Test it yourself...
In an empty parking lot...hang a sheet from a line that stretches between two poles that is high enough that your Volt will travel under the line...then drive toward the sheet and see if the Volt initiates braking...:)
 

·
Registered
Joined
·
5,782 Posts
It only works at street speeds unless ACC is activated. What speed? What conditions? Why do you think it doesn't work?

'Unavailable' indicates a fault like bugs (the icky kind) on the sensors.
 

·
Registered
Joined
·
5,410 Posts
It only works at street speeds unless ACC is activated. What speed? What conditions? Why do you think it doesn't work?

'Unavailable' indicates a fault like bugs (the icky kind) on the sensors.
You CAN reach highway speeds in a parking lot...:)
 

·
Registered
Joined
·
158 Posts
My Forward Automatic Braking on my 2017 Volt does not work. It doesn't seem to have ever worked. The dealer says they check it and never find anything wrong. I even had a message popup that said Forward Automatic Braking unavailable. (underline added)
Not sure what to do. Any suggestions?
FORWARD COLLISION SYSTEM UNAVAILABLE

This message displays when Forward Automatic Braking (FAB) has been unavailable for some time.

FAB does not need service. This message can display under the following conditions:
. The front of the vehicle or
windshield is not clean. Keep
these areas clean and free of
mud, dirt, snow, ice, and slush.
For cleaning instructions, see
Exterior Care pg. 314.
. Heavy rain or snow is interfering
with the object detection
performance.

This message may also be displayed if there is a problem with the StabiliTrak system.
See Traction Control/Electronic Stability Control pg. 192.

Someone posted a video of FAB in action not too long ago in a parking lot, don't remember how fast they were going.

My volt stops fine with ACC, which is different than FAB. I have never seen FAB work. As Loboc asked, why do you think it does not work?
(yes, ACC does not work in some situations, a different question)
 

·
Registered
Joined
·
4,405 Posts
On a 2017, you will notice 6 bright red lights light up your windshield from a HUD projector in the dash.

This is telling you a collision will happen if you do not take action. This is FCW, Forward Collision Warning and occurs before Automatic Emergency Braking.

The automatic braking happens at almost point blank from impact, and it will slam on the brakes violently.

A warning that the system is not working is often a dirty camera or radar. The camera cleaning is the top center of the windshield. That black area must be clean. The radar cleaning is the Chevrolet grill emblem which is smooth and plastic. Cars without radar do not have a smooth emblem.

What AEB looks like in a Cadillac:

https://www.youtube.com/watch?v=DK8gVr0x6_w

I have not experimented with objects in the Volt though. I've only seen the FCW when people cut me off. Once, the FCW came on, and my foot went to the brake, but I'm not sure whether the car got to the brake or I did first. I do know there was a very high probably of impact if the FCW didn't see the person pulling out of the left turn bay into the path. FCW saw the clueless driver before I did, but the entire event lasted under 1.5 seconds. If that sounds like a short time, that's 100 feet at 45 mph.
 

·
Registered
Joined
·
478 Posts
The automatic braking happens at almost point blank of impact, and it will slam on the brakes violently.

I do know there was a very high probably of impact if the FCW didn't see the person pulling out of the left turn bay into the path
AEB is not necessarily designed to prevent a crash. In some specific circumstances and speeds it may, but that's not the overriding design philosophy.

Think of AEB as an virtual crumple zone. It's designed to reduce the speed of the car at impact. If it can drop your speed from 40 to 20 prior to impact, that's a 75% reduction in impact forces and kinetic energy. Dropping from 60 to 40 is a 50% reduction in kinetic energy and impact forces.
It only kicks in when a crash is imminent (from a computer's point of view and reaction time, not a human's). And it's very, very conservative because it can be (no reaction lag for the computer), and so you don't get false alarms and shut it off.
Automatic emergency braking, also referred to as forward automatic braking, automatically applies brakes when the system detects that a front-end collision is imminent, to help avoid the collision or reduce the collision’s severity. - GM Website
 

·
Registered
Joined
·
5,782 Posts
to help avoid the collision or reduce the collision’s severity
This. AEB is not a substitute for driver braking.

I've had AEB activate on my ELR a couple times. One was a false-positive caused by a metal construction strip reflecting back at the car at night. Scared the crap outta my GF. I usually drive on ACC which has a much better braking algorithm.
 

·
Registered
Joined
·
6,677 Posts
I have only had FAB engage ONCE, and it was what I would call a "false positive" event. As I was approaching my house I pressed my garage door opener and kept going at 5 to 9 MPH as I turned into my drive way. My driveway is at a slight incline and I guess when I turn in the car read to slowly opening garage door as an obstacle and SLAMMED on the brakes. It was SUDDEN and scared the crap out of me. It took a weird set of circumstances to trigger it.

In all of my other normal driving I have NEVER gotten into a situation where the car needed to respond. I'm not that gutsy.

So to the OP how do you know the FAB isn't working?
 

·
Registered
2017 Volt Premiere
Joined
·
390 Posts
I have only had FAB engage ONCE, and it was what I would call a "false positive" event. As I was approaching my house I pressed my garage door opener and kept going at 5 to 9 MPH as I turned into my drive way. My driveway is at a slight incline and I guess when I turn in the car read to slowly opening garage door as an obstacle and SLAMMED on the brakes. It was SUDDEN and scared the crap out of me. It took a weird set of circumstances to trigger it.

In all of my other normal driving I have NEVER gotten into a situation where the car needed to respond. I'm not that gutsy.

So to the OP how do you know the FAB isn't working?
I received a message in the DID that it was unavailable after a dealer installed software update a while back. I had to do something with turning the cruise control off and on to get it back.
 
1 - 11 of 11 Posts
Top