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Hi all!

I recently purchased a low mileage Ampera with a full service history. No problems with it whatsoever.

However during the cold snap, I was forced to brake at speed as a lunatic in an ICE ran a red-light at a junction

I skidded on the ice, as I pumped the brakes before I finally stopped. My heart pounding and my face ashen, but thankfully both me and the Ampera were still in one piece.

However since the near-miss, I've found the Ampera has started skipping at low speed braking, i.e when approaching traffic lights. Just a slight loss of braking control when traveling at less than 10mph.

As I've owned the car for just over 3 weeks, I'm still not 100% sure if the aforementioned incident was responsible for this issue, or whether the Ampera was doing this prior, and my new-car tinted goggles ignored it...

Is this a common problem with Amp/Volts or is it something I should be concerned about?

Thanks
 

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dont thinks its common but it may be a broken or loose reluctor ring on a driveshaft.... best to get it checked
 

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Hi @JohnnyAmpera
I had a loss of braking for a second this morning when braking over wet man holes. That is caused by the traction control system which I think has not been perfected.

There has been talk on this and Volt forums of faults with the braking control module which has reportedly left the driver with virtually bugger all brakes for a second.

I do wonder if it is caused by a confused traction control as above but certainly should be investigated and I do believe that this braking module is considered part of the 8 year 100,000 mile Voltec system warranty that Vauxhall/GM supposedly gave the cars.
Good luck with that though.
 

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I notice a slight reduction in braking as the electronics swap over from regenerative braking to actual hydraulic brakes but that seems to be at very low speeds indeed - just before coming to a stop. I reckon this is because the discs are providing marginally less friction than the car expects. I simply increase the pressure on the peddle right before the vehicle needs to stop. (Makes smooth stopping a little trickier, but still doable).

Not sure if this is what your experiencing though - as I wouldn't consider my observation a fault as such.
 

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If the anti lock system kicks in does the regen switch off during braking? The LEAF does this and it is quite scary. Once you get used the car you tend to notice more of the tiny idiosyncratic knocks, rubs and buzzes. You can feel the regen and mechanical braking switching over/working together and this feels a bit weird just as you come to a stop. Maybe it's just that? Especially as you are new to the car.

PS Glad you were not killed by an evil ICE driver. An EV driver would have been more acceptable.
 

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If the anti lock system kicks in does the regen switch off during braking? The LEAF does this and it is quite scary.
Probably hit the nail on the head.
Braking over a slippy surface such as a steel drain cover would need regen off as well for the wheel not to lock.
This will cause a difficult scenario to control.
 

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There's no way you would have impacted the system by using it.

That being said, what do you mean 'pumping the brakes'? They are ABS; you press the brake pedal and hold it there as hard as you can. Doing anything else is causing problems for the system.

Anyhow, there is a transition at ~5mph where a solenoid actuates and the front brakes are then exposed to direct circuit pressure. You can feel this at gentle braking levels (which you are probably doing due to conditions) it feels like a little surge in braking force. If you are feeling something around this speed with gentle braking, it's probably normal.

There is actually a software update for the TRW braking system that Vauxhall UK have chosen not to disseminate, but if you ask for your dealer to check the software level of the main and slave brake modulator ECUs then they should return two numbers showing the software versions in each, one is probably out of date (it was on mine, and I had one of the later Amperas that came into the UK).
 

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I’ve had a near miss with mine,came down the lane and had to stop for a van coming up too fast.
I was in L and the car slid for a bit before the abs kicked in.
Loss of traction light came up and I filled my pants😂.
I’ve tried to repeat it but I’ve not been able to,it seems the car has to turn off regen and apply the friction brakes,but it takes a second,to switch over fully.
I’m now driving in the normal drive .
 

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I have been there as well. There is a road on my commute that has a drain cover just before the lights and if I brake hard when the road is wet and one wheel slides over the cover, you get an instant of no brakes at all and the traction light flashes.
It is unnerving to say the least and should be sorted by a recall to improve the software but it won't be.
The steering lock is another weakness that will impact on most if not all cars during their lives but is ignored in this country although other models in the US had fixes.
A "Low 12v Battery" warning would be a sensible addition as well but again we will not get one despite the car having a selectable message page for just such a warning that always seems blank. Does it ever display anything?

I bet you don't get these little quirks in software on a Tesla.
 

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Happened again today 😳
I think you need to get your car checked as there is a valve block in the braking system that has been known to fail.
It is covered by the warranty as it is associated with the Voltec drive system and has been mentioned here in the past but good luck using search on the new forum software.
 

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I've only ever experienced this 'slip' in the braking when leaving a car park downhill at walking pace and there is a manhole just near the end of the road that the front offside wheel runs over. I put it down to the temporary lack of traction on the cover. I have also noticed the very slight change in pedal feel when coming to a halt slowly where the regen transitions to the physical brakes.
 

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There’s a dip in the road where it’s skipping,tried it twice in the wet,exactly the same.
Took a run up at speed and slammed on using left foot.
Definitely not a breaking problem.
 

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I think it is a characteristic of the car as the salesman would say. I have had similar a few times and can reproduce the sensation on a particular roundabout entry which has a bit of a dip on the far side of the lane I honestly believe it feels worse than it is as you are expecting a deceleration greater than experienced very much like applying cycle breaks in the wet.
Any doubt though get them checked - it’s your brakes!
 

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It is interesting - I am currently enjoying training for my advanced driving test and my IAM coach/observer has noticed a few anomalies when I am driving the Ampera - the occasional "brake skip" being one of them. However, I think what he is noticing on most occasions is the braking effect of regeneration when I take my foot off the 'accelerator pedal' followed by a brief pause before I put my foot on the brake pedal. However there is also a very occasional skip between pure regenerative force and physical contact between brake pads and discs. Apparently, if an observer felt the same double braking effect (retardation-pause-retardation) in a conventional ICE vehicle, it would be heavily frowned upon.

Another Ampera quirk that has been mentioned is my apparent difficulty in holding a constant speed - typically 29 mph, 49 mph and 59 mph on restricted roads. Being one who always looks for the easiest solution, I have tried using Low and cruise control which seems to work most of the time but I have noticed that even with these settings the speed can creep up or down by a couple of mph depending on the gradient.

These cars never cease to entertain and intrigue!
 

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Low & cruise control seem to work pretty well for me - defo does a better job of restraining unwanted acceleration going downhill than Drive & cruise does! But I suggest you calibrate your speedo using an independent satnav; my Amp is generally 7% optimistic! 32 is a true 30, 53 a true 50, 64 a true 60 on my present tyres. Original., part worn Michelins were even worse, closer to 10% out. Driving at indicated 29, you might only be doing 26 & annoying those behind!
 

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Low & cruise control seem to work pretty well for me - defo does a better job of restraining unwanted acceleration going downhill than Drive & cruise does! But I suggest you calibrate your speedo using an independent satnav; my Amp is generally 7% optimistic! 32 is a true 30, 53 a true 50, 64 a true 60 on my present tyres. Original., part worn Michelins were even worse, closer to 10% out. Driving at indicated 29, you might only be doing 26 & annoying those behind!
That is a very good point - can the speedometer be adjusted? In the old days of mechanical speedometers, I used to send my MGB speedometer to a firm in Nottingham for servicing and calibration. This was because when the thing started to wear, the needle would start to swing to and fro so that it was difficult to determine the actual speed.
 

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I don't think you can calibrate it. GM made a deliberate decision to understate the actual speed. When I plugged my OBDII dongle into the car & drove, the canbus data reported the same speed my GPS was telling me! This must be why the built-in satnav won't display true speed; would no doubt cause litigation in USA!

I now use a dash-mounted satnav to give me my true speed, used when going through interminable 50-restricted roadworks, and loads of Warwickshire country main roads with similar restriction so thay can legally do less road maintenance than on 60-mph limited single-carriageway roads.
 
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