tpawlak

The Hill Start Assist on my 2015 C7 M7 stopped working several weeks ago. I made an appointment with the dealer next week and they asked me if my car was equipped with it. Based on their question I could use some help with the following questions.

1) It is not in my build order and the manual implies that not all C7s have it so how would I prove to dealer that my car has it and it is not working?
2) Since mine does not work anymore I do not remember if there is any display when it is engaged. Is there?

Thanks for any help...

Foosh

1) It's standard on all M7s. The clutch pedal isn't on your build sheet either.
2) There is no display for engagement.
3) Find a dealer who is educated.

Are you sure it's really not working? I don't notice it all the time, but every time I'm on a steep grade, I do. I always wait at stop lights in neutral with the clutch pedal released. When I depress the clutch pedal, and release the brake, it's always there on any kind of noticeable uphill grade.

Custom Corvette Accessories

Run...

...find a new Chevy Dealer

Regards
Chip

Foosh

The manual says that because automatic transmissions don't have it. How do you prove it? Point to the gear shift and clutch pedal.

Maxpowers

Does your e-brake work?

tpawlak

Thanks as I called on a Saturday to make my appointment when there are no or limited Corvette techs.

So it seems that all C7 Manuals from '14 to present have it but not automatics and there is no display to indicated when it is engaged.

Anyone have any idea why there is no indicator when it is engaged as it would seem to be pretty useful based on reading many of the Hill Assist threads...

tpawlak

No issues at all with my e-brake. Hill assist does not work on steep inclines but I can set the e-brake and it releases when I start to go with no issue.

Widgeon5

I don't have my manual in front of me, but the way mine seems to work is that hill assist is not engaged until you have selected first gear (or reverse) and applied (and released) the foot brake.

Foosh

You don't need an indicator for it, and you should be focused on the road, not head down. All you should be caring about is not rolling back.

Quite frankly, a competent manual driver doesn't need it at all. The only reason I know it's there is that I've tested it a few times by purposely not starting right away. I also feel a slight amount of resistance occasionally when starting on a hill, which is HA initially holding, then releasing.

I'm pretty sure it doesn't engage at all on flat or downhill grades.

tpawlak

You wouldn't have to "guess" if there was an indicator and there is no reason the indicator could not be in the heads up display if you are worried about looking "down".

Bill Dearborn

The way to check HSA is to pull to a stop on a steep hill. Hold the brake and put the car in 1st gear, keep the clutch in and then release the brake. The car should not roll backwards for a few seconds. After a few seconds the HSA will release and the car will roll backwards.

The biggest problem I have had with HSA is sometimes it holds more than it needs to and if I am not paying attention I will stall the car because the brake holds to well. Mine activates even on slight grades. I am pretty sure HSA is a function of the ABS and base brake system Vs an eBrake function. When you are on a hill, with the brake pedal pushed and the car stopped the brake control module detects that condition and applies brake pressure to the rear brake calipers. Just like traction control does.

Bill

Foosh

Actually, more to the point, you shouldn't have to "worry" about it at all.

tpawlak

Bill,

Appreciate the explanation. I will talk over with the Corvette Tech next week.

Foosh

Bill,

Does your eBrake release when starting normally?. Mine does, but others have reported their's do not. Similarly, I've never come close to stalling the car as a result of HA. I only feel the slightest amount of resistance before it releases. I've always assumed HA was an eBrake based system.

The point here is that it sounds like some eBrakes are harder to release than others. I wonder if there is some sort of adjustment.

pkincy

My daily commute has 3 very steep hills with either a stop sign or a stop light that will force me to stop on a steep hill. 2 of the 3 literally requited me to pull the ebrake up and coordinate releasing it with my clutch release and throttle position. Not all that hard, but darned inconvenient particularly when I was working and might need to be on a call or still having that morning cup of coffee. Drove me crazy in my C6Z06 which is why I bought the A8 this time. No longer have a problem.

Foosh

You don't need to do that on any version of the C7 M7 because of the standard Hill Assist feature, which is the subject of this thread. It holds the car automatically when starting on a steep hill.

mschuyler

True, but the fact is, whether you want one or not, there is no indicator. You started out with a practical question. Now you're being theoretical. That's not going to help solve your problem.

fumbling

This is my exactly problem with HSA, sometimes it causes a stall, so it creates a problem when it tries to solve another problem (rolling backwards). There is a definite difference in applying heavier accelerator pedal effort when HSA is on to get going, and it can stall if I just apply normal pedal effort. I'd just rather it had the option to turn it off.

Foosh

Fumbling,

As I said in post #14, my car does not do that, and I've never stalled it. It sounds like there is variability among cars. HA releases easily with normal pedal effort.

Similarly, I don't have to manually release the eBrake either, because it disengages automatically when I release the clutch and give it just a normal amount of throttle.

Bill Dearborn

My ebrake releases if I leave it on and start to drive away. Most of the time HSA just prevents the car from rolling backwards and a normal start will cause it to release. However, there are times on very slight upgrades where HSA isn't even needed for the clue less clutch users. It feels like the rear brakes are locked and you can literally feel the car straining to over come them. That is when you get the stall if you aren't prepared to compensate for the sudden unexpected resistance.

Bill