Friction brakes issue- 100% braking force - calipers?

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Luddite

Active member
Joined
Apr 11, 2017
Messages
44
Location
Scotland, UK
Hello All,

I rarely use the friction brakes - just when coming to a stop or in an emergency but today I was parking and applied the brake pedal lightly but I got full braking force and the car stopped suddenly and unevenly.

I reversed and slammed on the brake but it appeared normal. I tried it again in D and the same thing happened - it got full braking force when the pedal was only slightly depressed. I tried going back and forth a few times - it was fine in reverse but the same problem happened in D.
The braking was uneven and it seemed like the right side was braking more than the left and it made an almighty clunking noise.
Then I put it into drive but it did not move - put it into R and it unstuck.
I did this a few times and it now seems to be OK in Drive and reverse. - braking normally and no clunking.

Would I be correct in thinking this was just a stuck caliper - as the friction brakes are rarely used?
Is this a cause for concern or have I 'fixed' it by using the brakes?

The car is coming up for 7 years old now...

Thanks in advance!
 
Hmmm, had your car been sitting unused for a while? In our local rainy climate I always have to be careful in the first few drives after a layup, as the rotors get very rusty .
 
Hi Jray.

Car has been used almost every day but it has been quite rainy of late.

UPDATE: Just noticed this post from years ago on a Nissan Leaf forum -

http://www.mynissanleaf.com/viewtopic.php?p=176176#p176190

Seems that some people have experienced similar problems on the leaf and that it was software related?

http://www.mynissanleaf.com/viewtopic.php?p=240150#p240150

Also more info on this "grabby brake" issue below:

http://www.electricvehiclewiki.com/Brakes,_ABS#

I'll report back and try and remember to give the friction brakes a workout occasionally - with my driving style and the journeys I do, the friction brake usually only gets used at the end of every journey when I am parking.

Thanks.
 
Hi Brian,

Thanks for the reply
I haven't tried that yet but I will do. Brakes seemed to be a bit better today still squeaking a lot though.
I tested driving it in D up to 10mph and then braking gently - seems to be a little bit less grabby - but it seems to be the right hand rear wheel caliper that is sticking/grabbing.

It seemed to be a better today - just braking normally when I applied a little bit of force. The rotors have a fair amount of rust too but I thought it was strange that the issue only happened in D not reverse. No regen in reverse (that I know of) - so possibly a combination of rust/lack of use and the interpretation by the software?

Regen is working normally otherwise.
 
Our rear brakes are drum, not disc with calipers. Drums will behave differently than discs and can get grabby if loose, but driving back and forth a few times as you did should ratchet the self-adjusters a notch tighter...

You can get a closer look in this otherwise pointless i-MiEV 'brake cleaning' video.
https://www.youtube.com/watch?v=zxMeQlwCStM
The only reason to soak everything with brake cleaning solvent as he does is if you get grease on the shoes or drum friction surface. By cleaning off the grease that should be on the levers in that assembly, this fellow could actually promote rust on the lever contact points and springs, creating sticky, grabby brakes...
 
We get a lot of snow and slush and crust here in Quebec, Canada.
I also park the car lately in the garage - a breeding ground for rust.
Occasionally I'll get the stuck brake in the morning on start off.

Once and a while I'll run her up to highway speed on a safe unoccupied back road , put it in Neutral and brake quickly several times .
This seems to help clear off any rust or crust from the brakes.

(Now at 92,000 miles (148,00km) with original brakes
& yes I did a brake fluid flush 25,00 miles, (40,000 km) ago)
 
Luddite said:
Hi Jray.

Car has been used almost every day but it has been quite rainy of late.

UPDATE: Just noticed this post from years ago on a Nissan Leaf forum -

http://www.mynissanleaf.com/viewtopic.php?p=176176#p176190

Seems that some people have experienced similar problems on the leaf and that it was software related?

http://www.mynissanleaf.com/viewtopic.php?p=240150#p240150

Also more info on this "grabby brake" issue below:

http://www.electricvehiclewiki.com/Brakes,_ABS#

I'll report back and try and remember to give the friction brakes a workout occasionally - with my driving style and the journeys I do, the friction brake usually only gets used at the end of every journey when I am parking.

Thanks.

Funny that you mention this, as both IMIEVs in the family have had this issue. This is extremely hard brake force applied by a feather touch of the brake pedal.

Mitsubishi sorted this on both cars at the last service, and it was something to do with either a partially blocked filter, or a partially blocked breather tube on the brake vacuum pump . They didn't charge for it on top of the service, which was about £130 or something. It had nothing to do with the rest of the braking system, pads, disks, drums etc.

Both cars have since been fine. Try disconnecting part 1 here, and clean out the hose (part 2) and other areas with an air line - see if that helps:

35A: Basic brake > Brake Electrical Vacuum Pump

http://mmc-manuals.ru/manuals/i-miev/online/Service_Manual/2013/index_M1.htm
 
Thanks for all the info, guys.

It seems to be a little bit better and less grabby after trying to use the brakes a bit.


=============== EDIT======================

updated - I think the problem described below is the same one sandange was having with his shifter:
http://myimiev.com/forum/viewtopic.php?f=25&t=3830

==========================================

I did have a strange problem today though.
I stopped and put the car into park and the "gear" indicator started flashing P and the yellow exclamation mark came on. The gear indicator flashed in Park and Neutral and Drive, but not reverse.
I had another 10 miles to get home and I didn't want to restart the car in case I couldn't get it started again.

As soon as I drove off, the turtle light came on regen was disabled.
I had never experienced turtle mode before so this was a new one for me. Could do 35-40mph at the maximum on a 60mph road. It was a little dicey!

As soon as I got home, I restarted the car and all seemed OK. I took it on a test run and all seemed well.


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https://postimg.org/image/fp3dx6gfp/
https://postimg.org/image/xf52i8ovp/

Thanks
 
Your warning light experience sounds familiar to the problem I had.
Keep in mind that my Miev is a 2014 North American edition..

Did you watch the video recordings of my problem from my posting that you linked to above?
How does it compare to your problem?
 
sandange said:
Your warning light experience sounds familiar to the problem I had.
Keep in mind that my Miev is a 2014 North American edition..

Did you watch the video recordings of my problem from my posting that you linked to above?
How does it compare to your problem?

Thanks I did. I found your original post through your comments on the you tube video. Very useful, thanks. :)
I only experienced this problem once but it does look like it is the same issue.
The pedal is stiffer and does not seem to move so easily and sometimes squeaks going between N and D.

I put it into P but it was still registering Reverse and I had to move it back to R and back to P again. This was when the warning light came on and the P started flashing in every drive mode except R.
I decided to drive home instead of trying to restart as I was scared it may not restart. As soon as I applied power, the turtle came on and I had no regen at all so the brakes got a bit of a workout!

I can't remember if KIWIEV posted a video on taking apart the shifter to clean and lubricate it. Can't seem to find it on his you tube channel but I may have to do that and see if there is any dirt in there.
 
Luddite said:
Hello All,

I rarely use the friction brakes - just when coming to a stop or in an emergency but today I was parking and applied the brake pedal lightly but I got full braking force and the car stopped suddenly and unevenly.

I reversed and slammed on the brake but it appeared normal. I tried it again in D and the same thing happened - it got full braking force when the pedal was only slightly depressed. I tried going back and forth a few times - it was fine in reverse but the same problem happened in D.
The braking was uneven and it seemed like the right side was braking more than the left and it made an almighty clunking noise.
Then I put it into drive but it did not move - put it into R and it unstuck.
I did this a few times and it now seems to be OK in Drive and reverse. - braking normally and no clunking.

Would I be correct in thinking this was just a stuck caliper - as the friction brakes are rarely used?
Is this a cause for concern or have I 'fixed' it by using the brakes?

The car is coming up for 7 years old now...

Thanks in advance!
Your problem will be one of the rear drum brakes binding up. I had this exact problem on mine a few months ago, and I discussed it in detail on SpeakEV:

https://speakev.com/threads/p-ion-grabbing-brakes-just-before-stopping.92881/#post-1665961

The symptoms are at low speeds the lightest touch of the brake pedal will cause one of the rear drum brakes to lock solid - on mine it was the left side. This only happens in forwards not in reverse. In fact on one occasion the drum locked so completely that I could not drive forwards and had to reverse to get it to unlock, much as you did.

I gave the rear drums an overhaul and clean and it has 90% fixed the problem - most of the time it works perfectly now but occasionally in cold wet weather the rear left drum still gets slightly "grabby". This is probably because moisture changes the frictional coefficient of the shoe friction material, and cold temperatures cause the drum to shrink slightly - this leads to the shoe grabbing at the edges causing "spragging" due to an increase in the "shoe factor" of the leading shoe.

I have not had a chance to go back and do any more work on the drums, and as they are working perfectly nearly all the time now I probably won't bother until it starts misbehaving again. Very slightly tapering off the leading and trailing edges of the friction material on the shoes (to reduce their effective radius) with some sand paper is probably all it needs.
 
Luddite said:
I did have a strange problem today though.
I stopped and put the car into park and the "gear" indicator started flashing P and the yellow exclamation mark came on. The gear indicator flashed in Park and Neutral and Drive, but not reverse.
I had another 10 miles to get home and I didn't want to restart the car in case I couldn't get it started again.

As soon as I drove off, the turtle light came on regen was disabled.
I had never experienced turtle mode before so this was a new one for me. Could do 35-40mph at the maximum on a 60mph road. It was a little dicey!

As soon as I got home, I restarted the car and all seemed OK. I took it on a test run and all seemed well.
Is the gear lever feeling a bit stiff and "springy" pushing it into drive by any chance ?

What you're reporting will be a failed coherency test of the gear lever position switches which are mounted on the gearbox at the rear of the car.

On older models of the Ion (pre 2012 I think) there are two separate gear position switches - one directly on the shaft that goes into the gearbox near where the bowden cable attaches, and a second one further along the gearbox which is driven by a ball jointed link rod.

The purpose of having two switches is redundancy - allowing the ECU to know if there is a problem with one of the switches, as they should report the same gear position at all times.

If the two switches report a different gear position for more than about 3 seconds it sets a fault code in the EV-ECU which brings on the yellow exclamation mark and causes the gear position letter to flash - indicating that the car is unsure what gear position it is actually in.

I had this issue recently and although I was still able to drive the car despite the warning I found it prevented the car from being charged, so of course it was urgent that I find and fix the problem.

Using my Lexia diagnostic tool I confirmed that in the Park position the primary switch was reporting Park but the secondary switch was still reporting reverse - and the cause was that the gear lever linkage assembly on the gearbox had partially seized up and become stiff due to salt water spray, which is apparently a very common problem with these in the UK.

The gear lever stiffness came out of nowhere in less than a week of rainy weather after a year of no problems.

This stiffness was making the gear lever feel "springy" when trying to engage Drive or Park and was preventing the switches from both going fully into the Park position.

The solution was to give the pivot points and ball joints on the linkage a thorough dosing of spray grease, and I'd recommend it's done on a yearly basis.

I posted a full description and photos in the following speakev thread:

https://speakev.com/threads/c-zero-ion-charging-failure-due-to-stiff-gear-lever-mechanism.98153/

(sorry to keep posting links to another forum mods, but I really don't want to copy and paste all the text and pictures)
 
DBMandrake said:
I posted a full description and photos in the following speakev thread:

https://speakev.com/threads/c-zero-ion-charging-failure-due-to-stiff-gear-lever-mechanism.98153/

(sorry to keep posting links to another forum mods, but I really don't want to copy and paste all the text and pictures)


Thanks for all your really useful info and your replies to my other posts.
I had a look at that thread a few months ago and was very useful. When I took the car in for its MOT they greased up the points at no extra charge. The shifter is working like a charm now but absolutely agree it should be something that is done every year if not more often in climates with road salt in the winter.
Have you thought about undersealing the car? Looks pretty corroded in places. Mine is fairly similar corrosion wise.
I realised I had the wrong thread and posted some more info here:
http://myimiev.com/forum/viewtopic.php?f=25&t=3830&p=35161


In regards to the brakes, the issue does sound similar to yours with the drum brakes however I jacked the car up and the left front wheel was rough to rotate like the brakes were stuck on and it did get hot after driving. Again your post was really informative. Some of it is beyond my scope of DIY but extremely helpful when talking to my trusted mechanic :p
After going into neutral and giving the brakes a workout, it seems to have stopped and does appear better in the drier warmer weather I am also trying to use the friction brakes occasionally! Roll on summer :D
 
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