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View Full Version : Brake lite comming on w new brakes


chads
02-23-2013, 10:30 PM
I have a brake light comming on the dash. It is generally off when I start it but after I apply the brakes a little hard it will come on almost every time.
The brakes were installed by the dealer prior to purchase.
I took a look under there today and saw a wet spot near the right front wheel I am wondering if the computer will sense a leaky hose or something.
I have a 2006 140 short.
It has been cold and snowy lately but having good weather today and tomorrow so I want to look into it.
If I need to change the hose out is there anything I need to wach out for that may mess up the sensors etc.
I have some old dot 3 brake fluid is that ok?
Chad

Aqua Puttana
02-24-2013, 12:22 AM
I have a brake light comming on the dash. It is generally off when I start it but after I apply the brakes a little hard it will come on almost every time.
The brakes were installed by the dealer prior to purchase.
I took a look under there today and saw a wet spot near the right front wheel I am wondering if the computer will sense a leaky hose or something.
I have a 2006 140 short.
It has been cold and snowy lately but having good weather today and tomorrow so I want to look into it.
If I need to change the hose out is there anything I need to wach out for that may mess up the sensors etc.
I have some old dot 3 brake fluid is that ok?
Chad
The wet sounds like you have a leak somewhere? A low level in the reservoir will turn on the dash light. Check the master cylinder fluid level. The fluid may slosh a bit when braking hard.

I wouldn't hesitate to top off with DOT 4. I would only use DOT 3 in an emergency.

The formulations of DOT 3, DOT 4, and DOT 4+ (or whatever description they add) are completely compatible except that the higher numbers have higher wet boiling point characteristics.

NOTE: DOT 5 is NOT compatible. DOT 5.1 is fine, but not easily found so likely not a choice anyway.

SECOND NOTE: Valvoline sells a product labelled DOT 3 & 4 Brake Fluid. I believe that it is just DOT 4 fluid which for marketing reasons they have named 3 & 4 to save confusion on the part of consumers. One of the DOT brake fluid specifications includes that the DOT 3, 4 family be backward compatible. (There may be some older brake systems which cannot tolerate the borates contained in the DOT 4 formulation, but that doesn't apply at all to the Sprinter to the best of my knowledge.)

http://www.valvoline.com/products/brands/valvoline/dot-3-4-brake-fluid/28

It should ne noted that MB recommends DOT 4+ brake fluid. DOT 4+, or other descriptions added to the DOT 4 specification number mean different things to different manufacturers. One common characteristic is that the 4(x) has a higher wet boiling point. DOT 4 is generally lower for that specification as compared to plus.

I submit that topping off with DOT 4 fluid is a better move than waiting until DOT 4+ fluid is eventually found. If the fluid reservoir goes empty it just might ruin your day.

vic

pgr
02-24-2013, 01:02 PM
After power washing my van a few days ago (including the wheels) the brake light comes and goes sporadically. I just did the new pads & rotors 3k miles ago so I suspect water got into the sensors on the wheels and is causing it. It was too cold and wet to check it out before going on vacation so perhaps when I get back in a week it will be fine.

I would take Vic's advice and check the brake fluid reservoir also. It doesn't take much to make the light come on!

Aqua Puttana
02-24-2013, 01:20 PM
After power washing my van a few days ago (including the wheels) the brake light comes and goes sporadically. ...
My T1N brake light would come on only when on vacation in the Florida Keys. Surprisingly it seemed to happen when the dew was very heavy, and not when it rained? Inspections never revealed anything.

When I changed my rotors, pads and sensors I found one sensor wire had a tiny pinhole in the wire insulation. Since installing the new sensors the brake warning has remained off. FWIW. vic

chads
02-24-2013, 02:04 PM
Thanks for the update on the dot 3-4 valvoline.
I had it in my hand today at walmart and put it back.
The rest was dot 3.
How important is the brake fluid flush? And what should it cost to have done?

Chad

chads
02-24-2013, 02:55 PM
I went out and got under there.
Looks like the shock is leaking and the brake is dry.
The cover for the shock fell down wonder if that made any diffrence?
Still have the light.
Chad

Aqua Puttana
02-24-2013, 03:09 PM
...
How important is the brake fluid flush? ...

Chad
If the fluid is not changed regularly and the moisure levels build up there are reports that you increase your chances of problems with the ABS system related to corrosion.

DOT 4+ fluid and a special operation routine of the ABS system is recommended.

I have no idea of expected cost.

vic

Shock leak?

Is the master cylinder brake fluid level OK?

chads
02-24-2013, 03:18 PM
The master cylinder is full and the caliper and everything over that way is dry.
The wetness is on the lower half of the strut I think the upper seal is leaking and since the cover is loose it fell to the lower half covering up the leak till the exposed bottom half ot the strut.
I am going to have to look into the wear sensor wires they seem sensitive.
Is there a easy way to get them out without pulling the caliper?
Now I think of it I should check the rear brakes,I can see the front are new but not sure on the back.
I was at advance auto a couple of weeks ago and the light was off at start up and he checked for codes but nothing came up. Do the generic readers show a code like this. Or would it only work if the light was on.

Chad hoping I can locate what wheel with a scanner before digging deeper.

Aqua Puttana
02-24-2013, 03:33 PM
...Do the generic readers show a code like this. Or would it only work if the light was on.

Chad hoping I can locate what wheel with a scanner before digging deeper.
MIL on or off very few generic scan tools would be able to access a vehicle ABS module for codes. (Probably insert "none" for "few" when it comes to a Sprinter.)

Maybe the rears are your problem? vic

chads
02-25-2013, 10:42 PM
I took the rear wheels off today and the rear brakes were worn out the one sensor was making contact and the other fell off the pad and was hanging there.
I picked up a set of pads and put them on took about 15 min after I got back with the pads really easy I thought.
I used a hose crimper and bled off the excess fluid as I compressed the cylinders. I guess that is supposed be better than pushing junk back to the abs. I polished and greased the pins to avoid any issues binding.
I had a hard time finding a allen that fit, the metric wouldn't work at all I had a 6 and 8 no 7.
The english sizes sort of worked.
Then I got out the torx sizes and one fit just right.
I ran into that on the transmission plug too. Is everything supposed to use torx even if it looks like a hex?
Chad

Ciprian
02-26-2013, 05:04 AM
I took the rear wheels off today and the rear brakes were worn out the one sensor was making contact and the other fell off the pad and was hanging there.
I picked up a set of pads and put them on took about 15 min after I got back with the pads really easy I thought.
I used a hose crimper and bled off the excess fluid as I compressed the cylinders. I guess that is supposed be better than pushing junk back to the abs. I polished and greased the pins to avoid any issues binding.
I had a hard time finding a allen that fit the metric wouldn't work at all I had a 6 nad 8 no 7.
The english sizes sort of worked.
Then I got out the torx sizes and one fit just right.
I ran into that on the transmission plug too. Is everything supposed to use torx even if it looks like a hex?
Chad

It's been a while since I did the brakes, so I don't know if they are allen or torx. But on the transmission plug it is allen (I think 5 mm) and the transmission pan bolts are torx.

Aqua Puttana
02-26-2013, 11:12 AM
... I had a hard time finding a allen that fit, the metric wouldn't work at all I had a 6 and 8 no 7.
The english sizes sort of worked.
Then I got out the torx sizes and one fit just right.
I ran into that on the transmission plug too. Is everything supposed to use torx even if it looks like a hex?
Chad

The brake pins should be Allen. 7 mm.

I have used Torx on Allen by mistake. Not the best move, but on larger size fasteners if things aren't too tight I believe it has little risk of permanent damage.

Some of what I learned about my brakes is in this post.

http://sprinter-source.com/forum/showthread.php?p=95072#post95072

vic

chads
02-26-2013, 11:54 AM
Where do you get the 7mm allen?
The three Ecklind sets I have skip that one and the auto parts store sets skipped it too?
Chad

Aqua Puttana
02-26-2013, 12:06 PM
Where do you get the 7mm allen?
The three Ecklind sets I have skip that one and the auto parts store sets skipped it too?
Chad
First...

Altered Sprinter be warned.
Richard,
Do not click on the link below. You will likely find the information contained there as disturbing as you do a picture of a dirty Sprinter. :tongue: :hugs:


http://www.harborfreight.com/catalogsearch/result?q=allen+socket

vic

chads
02-26-2013, 01:58 PM
Sounds like next time I am over that way I will have to get a cheap set to fill the gap.
Thanks Vic.
Chad