PDA

View Full Version : Brake fail


madmac666
09-13-2018, 03:16 PM
Hi from Scotland. please excuse my first post being to ask a question!

I have a 2011 sprinter 319xlwb V6, one of many I've owned over the years. The other day I had to touch the brakes to lose a bit of speed after someone pulled out in front of me, nothing dramatic but when I put my foot on the brake the pedal didn't move at all, like something was stuck under the pedal! I put more pressure on and it still didn't move and the van didn't slow at all. I pushed with both feet as hard as I could and it finally moved. By this time I was very close to the other car but the ABS came in and I managed to slow enough to avoid a collision.

It's never shown any signs of this from new ( now 140k miles) and it hasn't done it since. Obviously this is a bit worrying and it's eroded trust in the van. I've checked the master cylinder, servo and vacuum pump and all seem fine. It wasn't like the servo had failed as I would still have had brakes, the pedal was solid in it's rest position and I had zero brakes and lost no speed. I was just about to pull the handbrake when the pedal finally moved.

I suspect the ABS pump as I can't think of anything else that could have been the cause of such an event.

Has anyone heard of this before? If so is there any information anyone can add to help diagnose and make sure it doesn't happen again?

Thank you

Donald

CJPJ
09-13-2018, 03:32 PM
No mad mac 666 that hasn't happened to anyone before - just you.

Bobnoxious
09-13-2018, 03:42 PM
Is Scotland humid? When was the last time the brake fluid was changed?

ptheland
09-13-2018, 04:17 PM
I'd check for physical obstructions on the brake pedal. Did something get jammed behind or around the pedal?

autostaretx
09-13-2018, 05:41 PM
... and keep in mind that you can grab the parking brake handle when you even *think* there's a braking problem.
(and (if you have enough hands/fingers), start the Hazard flashers since your brake lights won't be coming on)

You might have the Sprinter scanned for problem codes... it could have been the ABS (anti-lock braking) module mis-behaving.

--dick

madmac666
09-13-2018, 05:57 PM
Thanks for your replies

Brake fluid was changed about 6 months ago along with front calipers and new discs all round.

Definitely nothing obstructing the pedal. It did this the once and brakes have been as normal immediately after and since.

I didn't dream it, it definitely happened. It took huge force on the pedal to move it

I can't imagine any event that would cause an ABS pump to block fluid to all 4 calipers. I'll check for any fault codes though.

Worrying this could hsppen for any reason!

Cheyenne
09-13-2018, 06:25 PM
From your description the problem sounds to be more mechanical than hydraulic so I would start by examining the pedal and push rod for any signs of wear or abnormal alignment, possibly even stripping the entire pedal down to examine it in fine detail.

Many years ago I had a high mileage BL car (remember them?) and the hole through the pedal that the clevis pin acted in had gone seriously oval along with steps in the pin and this occasionally acted very unusually!

Keith.

madmac666
09-13-2018, 07:48 PM
Keith, I pulled out the clevis pin, checked the pedal movement, clevis pin and pushrod and it all looks good.

I have good experience of braking systems but not had any ABS pump problems in any car or van so I'm not clued up on the electronics of the sprinter, Could it have been a unique series of events causing the ABS pump to stop fluid moving through it momentarily? I would have thought that there was a failsafe to make sure that didn't happen with a braking system

I've done about 500 miles since and it's been faultless

I'm going to check for codes now I have my scanner back

Appreciate your input :thumbup:

madmac666
09-13-2018, 08:47 PM
Have found under ESP category '5731 event - no fault' stored. There are other codes relating to cam sensor and dpf but this 5731 would be the most likely to relate to an ABS problem?

I can't find much with a Google search :frown:

Aqua Puttana
09-15-2018, 02:01 PM
Have found under ESP category '5731 event - no fault' stored. There are other codes relating to cam sensor and dpf but this 5731 would be the most likely to relate to an ABS problem?

I can't find much with a Google search :frown:
Have you checked the operator manual?

I don't know whether the NCV3 models log a history for every ESP "event", but not a failure or real problem as such. A simple "event" log could be the programming now. My understanding is that as time goes by vehicles have more and more information stored. It is getting similar to the Black Box recorders in aircraft.

A call to a dealership might help, if they are willing to discuss and not just schedule a service appointment.

:cheers: vic