ABS/VDC Self Test on Startup noise

[Couz]

Ok, so I know we're supposed to hear a normal clunk/pump on startup which is the self test.

But over the weekend in combination with the normal self test noises I also hear on occasion a spring contracting noise along with the clunk/pump.

The spring release noise literally comes at the same moment as the self test so I'm assuming something is going on there with the self test.

No other symptoms, the car is fine.

Just this noise started over the weekend first time I hear it with 2500 kms on car.

Again, its very intermitent and I can go 15 or so startups without hearing it.

Mostly happens on cold starts, and if I stop the car and restart it right after I hear I will not hear it.

I park on a downhill if that has any impact.

Any know what this noise can be?

[Couz]

Someone must have an anecdote or two concerning noises with the ABS/VDC self teast right at startup.

Is it louder at times, different noises sometimes.

[kerrton]

Yeah I remember hearing that spring noise on occaission, and I know that I read an explanation about it somewhere on this forum several months ago but can't find it. I remember that not all self checks/diagnostics occur every time you start it up, some such as this spring noise, happen only intermittently or "when needed", from what I remember about the post. The bottom line was that it was normal and nothing to worry about.

[Couz]

thanks Kerrton.

I always heard the regular clank/pump consistently but the spring noise right at the ABS/VDC self test was intermitent and that's what got me concerned.

But I knew the spring noise was related to that self test because it literally happened at the moment of the clank/knock.

Those self test noises seem to vary so much, sometimes its louder, sometimes I barely hear it, sometimes I hear the spring noise, sometimes i hear two clanks or one clank etc...

[Couz]

Can anyone explain why on some days the self test makes a spring contracting noise and on some other days not.

As Kerrton said in this thread its normal and i'm 100% sure its related to the self test, the spring unwinding sound occurs exactly when the self test is supposed to occur and replaces the clunk, I have no other issues after that sound.

The degrees of sound vary also, some days its louder than other days.

I'd love to find the thread Kerrton read regarding this issue being normal or whoever posted it.

Basically, if its a self test why do the sounds vary from day to day, meaning, cold mornings I'll hear the spring unwinding sound, when the car is started up when warm its just the clunks....I always get a sound that's for sure, but the sounds vary...is that normal?

I found a previous thread with Phillipa responding but it was just about the noise, it wasn't regarding why its intermittent and why sometimes it sounds like a spring and others a clunk or click.

Modified by Couz at 9:02 AM 5/20/2009

Modified by Couz at 10:47 AM 5/20/2009
Modified by Couz at 10:52 AM 5/20/2009

[Couz]

I got this from an Infiniti/Nissan tech.

Yes the "spring unwind" type noise is a normal noise. Once the self test is done it is normal to hear no further noises related to the system. Usually you'll only hear the noise on the first cold trip of the day, but this isn't always the case. And yes the noise varies from a thump to a "spring unwind".

I just find it weird that on some days its a clunk and on others i hear a spring unloading noise.

Anyone know why ?? Philippa ??? I know you answered questions about this in the past.

Modified by Couz at 5:52 AM 5/21/2009
Modified by Couz at 5:52 AM 5/21/2009

[philipa_240sx]

What you are hearing are the ABS solenoids cycling while the test is being done. My Rogue does it and so does my '03 Altima. It's normal and unless it persists after the first minute of driving, I would not worry.

BTW, if you are concerned about the ABS self test noises and the CVT rattle, they are unrelated. The CVT rattle usually occurs once the vehicle is warmed up and when slowing to a stop. The ABS self test only occurs immediately after starting the vehicle and driving the first few metres.

Couz, I know I've said it before... Just relax and enjoy your Rogue!

[kerrton]

Bump, this is good info. for owners who may not be familiar with this noise.

[crankthesiren]

Hi , informative thread, wondering if anyone can help me investigate something further on this VDC topic.

have a rogue 09:
-brake fluid went down to min i topped it off.
- I did not notice whether or not VDC /slip light was on or not before hand
-since then after ignition the VDC self-test seems to fail (i hear this motorized disengage sound, and the slip / VDC Offf light both come on)
-I read that this might be due to worn out brake pads or rotors
-I replaced my rear brake pads and rotors
-VDC Off /Slip lights still come on, same motorized sound

I am assuming that the self-test diagnostic for VDC is failing and the system shuts it down after ignition and I move the car at very low velocity.

Is there a way to find out what diagnostic tests are running so I can find out what exactly is failing?
I have found this page that describes some of the ABS tests, just wondering if there are more:

http://www.alldatadiy.com/alldatadiy/DI ... /178004414

Thanks