Check Brakes At Next Stop

Check Brakes At Next Stop

VNL 660 message

davelinde
05 May 2011
09:33 PM
When I bought my 660 I was getting this code on startup.  The truck had been singled but the original 6M ABS control was still installed and we (me and the seller) assumed this was the reason for the message.  I bought a 4M ABS control, installed it, and the message disappeared as expected.  I did have a little wonder why I got the "check brakes at next stop" instead of an ABS light -- but all was good. Well, today I needed to move the FW and fired up the truck, to my dismay I got the "check brakes at next stop" message again.  I hitched up and moved the FW and
the message went away before I was done (it never used to clear itself before so this is different).

I'm about to take an 1,100 mile trip with another 2,000 miles not too much later. I don't need issues on the road -- but, what am I looking for?  What triggers the "check brakes" message on the computer?  I hate to pay $94/hr. for someone else to poke at this - but I do not have a lot of time to play myself.  If I had some kind of idea what I was checking I could probably get a mechanic to look at it on the side too.  I just hate to go that route if I'm unclear about what we are looking for and/or may fix

Ray_nomad
05 May 2011
09:57 PM
Got a similar problem with a right rear ABS sensor.  When it get real cold out sometimes I get that message.  When the ABS "finds" it and you travel (could be wrong about the speed) 4MPH it clears.  I need to check mine now that the weathers warmer.  Even if it clears it should "post" a code in the diagnostics with an INACTIVE tag.
Bill B
05 May 2011
10:19 PM
In my case, I caught a wheel sensor on a tool in my hip pocket and pulled it a way a bit from the tone ring (1/4" or so).  Check to make sure that nothing snagged one.

Other than that, Ray is spot on.

marvmarcy
06 May 2011
02:40 PM
I get the check brakes along with the TCS light.  I can clear the check brakes easily but the TCS light stays on until I shut down.  It is gone as soon as I restart.  It seems to be a wiring issue or possibly an ABS sensor because it usually happens in rain or high humidity and seldom happens when it is hot and dry.  Braking on washboard road can also trigger it, but it often clears itself.  I also can get a check engine warning and red shut down light if my foot slips off the throttle, but it goes away as soon as I work the throttle normally. I think these trucks just have their own
quirks.
davelinde
06 May 2011
05:19 PM
It is possible I've got something up with an ABS sensor, when I first installed the 4M control I decided to test the ABS.  So I found some clear road and stepped on the brakes hard (bobtail).  The first time was fine - the rears did lock/skid but they both modulated OK (I guess you don't feel anything in the pedal) and left a clear skid/roll/skid/roll/skid/roll.  However a couple more tests were not as good -  I locked up one side solid.  Last week when I brought the truck for service it was working fine and they told me the sensors do that sometimes.

I am assuming that all codes are coming from the ABS controller and the fact I've got a dangling connector there should not matter (for the missing axle).

I'm still learning the quirks. This board helps a lot.

MacDaddy
06 May 2011
10:51 PM
Hmmmm.
If it's a fault with basic ABS, the yellow ABS lamp should be lit solid.   Then you can get codes to see if it's sensors, modulators, etc.  If it's a fault with the traction control system, the TCS lamp will be lit solid.  Again, there should be specific codes related to ABS.

What I can't remember for sure is, is there some other fault that will drive the "check your brakes" message.  Have any of you seen that message without having an ABS or TCS fault?

davelinde
07 May 2011
11:23 AM
Right, that's what I'm wondering.  No ABS or TCS lights, just the check brakes message.  It's back again today and not clearing itself.
Ray_nomad
08 May 2011
10:44 AM
Might be a dumb question, but are the ABS and TCS lights working?

Rebuilt or new ABS controller?

Any codes under the diagnostic/ABS ECM? I would think there should be

davelinde
08 May 2011
05:11 PM
No dumb questions, ABS and TCS lights work.

Rebuilt.

I need to figure out where to find the next layer of codes in there...

MacDaddy
08 May 2011
06:12 PM
Well, the ABS lamp isn't lit, and the bulb works.  You can also pull up the faults via the driver's display panel.  There you can get the faults in English or SAE fault codes i.e. MID136 for ABS, yada yada yada.

If you have no codes there, I think you've eliminated ABS as the source of the warning.

davelinde
11 May 2011
02:29 PM
So now I'm not so sure.  The TCS lamp works and there is AN ABS lamp working, but I think maybe that is for trailer ABS - the icon is not clear to me.  So maybe one of the blank positions in my dash is a missing/burned ABS lamp.
davelinde
23 May 2011
07:48 PM
I decided not to mess with this before my last trip and did 1,100 miles with it fine.  The odd thing was that it came on and cleared and came on and cleared at 6 or 8 times in two days.