Spark EV Braking Question

[MrDRMorgan]

I have been noticing that when I apply the brakes in my 2016 Spark EV, slowing down seems normal until just before the car stops. Just before the car stops, I here an audible "clunk" and experience what feels like the brakes grabbing. Anyone else have this experience or can identify possible causes? My 2014 spark EV does not have this problem.

 

[JAMMan]

It's definitely the car switching from regenerative 'braking' to actual friction pad brakes because regen can only slow the car to about 2-3 mph. Perhaps the software version in your 2014 is better than your 2016, or perhaps there was an update to the software that you're missing from the dealer?

I don't feel mine 'clunk' on my 2015 but I absolutely can tell when it shifts from regen to friction pads.

Mine feels different depending on the scenario, for instance if I was using regen only alllllll the way up to the last couple feet and barely rolling along the transition is pretty smooth. If I'm braking with medium force I feel the transition more abruptly. If I'm braking hard I feel the car using the friction brakes PLUS regen and the transition is completely unnoticeable because both brakes are engaged.

Sometimes, at low speeds as I'm using the brake pedal lightly and get down to single digit speeds, the car STILL lurches forward as I press the brake harder and harder until I have to slam on it for it to engage the friction brakes (b/c regen can't get you down to 0 mph) and then it's violent and my wife gives me a side glance and I say, "It's the stupid car's blended brake system, sorry!"

I wish they would have let the regen be attached to the accelerator pedal and friction brakes to the brake pedal only. That way I could use either one discriminately rather than the system choosing for me and often choosing wrong or harshly.

 

[ElDobro]

About 2-3 weeks ago, I noticed front end noises that I don't recall ever hearing before. They're fairly prominent when parking. I checked everything I could in the front end to see if something loosened up, but nothing. I contacted someone I know at the Chevy dealer and he came up with this.
PIC6122A Spark EV Noise When Braking Or Backing Up With Or Without DTC P061B Dated Jul 5, 2019.
Basically, it comes down to seeing if the HPCM T6 is up to date with programming.
Next time I get a chance, I'll have the dealer check for updates.

 

[jeasterday]

Yep, I have the same on my 2014. Freaked me out the first few times, then I just got used to it. It's a feature!

 

[boatbum11]

You might be hearing the pedestrian alert system that engages when the vehicle is traveling 18 mph or slower. It's a white noise that sorta sounds like a turbine from a long distance away, that emanates from a speaker at the front of the car.

I find it rather annoying when I have the windows down in good weather, but I do have exceptionally good hearing.

 

[ElDobro]

This is definitely the brakes, you can hear it on both sides of the car.

 

[Kermit]

My brake does the slight jerk at 3mph as it transitions from regenerative to the actual brakes. I saw a video where someone had a similar issue with a clunk and it was something rolling around in his glove box that actually made the noise when he hit the brakes hard enough. It may be worth checking out?

 

[SparkPlugEV]

The transition from regenerative braking to disc brakes is most scary when driving downhill in the rain on stock tires. The car loves to hydroplane when the disc brakes kick in. That's why I just upgraded my wheels and tires. Those low rolling resistance stock tires are not made for wet weather driving in the Pacific Northwest.

On my 2016 Spark EV I find the transition braking less noticeable when driving in L (higher regenerative braking mode). That's why I pretty much drive on L all the time except perhaps on highway driving when I want to coast a bit at higher speeds when I let off the pedal a bit.

 

[ElDobro]

I had the brake update done today and it feels like things are a bit smoother when slowing down. I'll have to see how it feels during my commute next.
The tech told me that besides updating the HPCM T6, the update also included updating the HPCM2 and the motor lubricating oil pump control.

 

[Porsche]

I wish they would have let the regen be attached to the accelerator pedal and friction brakes to the brake pedal only. That way I could use either one discriminately rather than the system choosing for me and often choosing wrong or harshly.

Actually, they did. What you're looking for is exactly how the car works if you shift it into LOW instead of DRIVE. It's "one pedal" driving; releasing pressure on the accelerator engages the regenerative braking, even puts on the brake lights. Well, maybe not quite exactly but pretty close.
You'll still get more aggressive regenerative braking from the brake pedal before engaging the friction brakes, but otherwise, just what you're looking for.