TypeRod

So today in Northern VA, it got to a high of 20 degrees F. I left work and my "BRAKE" light did not go out. Parking brake was fully released. The light would turn off and on as I was braking. The pedal was nice and firm. So I had been having this situation every winter, and a few months ago, I replaced the styrofoam float that lets the level sensor if the fluid is low. As sure enough as the engine warmed up the "BRAKE" light stayed off, but when I got home I checked the level anyway, and it seemed a bit low. I added more fluid. So I will keep an eye on the level, but I have a feeling my brake master cyl. may need replacing. Is it possible for it to leak within the booster? I took a quick glance and did not see any drips or signs of leaks around the MC or underneath where fluid may drip onto and collect.

Any suggestions as to what to look out for? Is it probably the MC? My R is 18 years old this year and has ~246K on it. This is the original MC still. If it is the MC, should I replace the whole thing or can I just replace a seal?

Thanks in advance!

RTW DC2R

IIRC, the MC and Booster can leak into the interior by the pedals. Have you checked that area? Or any leaks at the bleed screws or corrosion at the hard lines?

Does the light only come on after youve used the parking brake?

Heres some MC and Booster checks:

yoshi234

My '00 CRV used to do the same thing only on cold days.

y shi - who just learned to ignore it since nothing else was wrong w/the brake system

BlackAckeR

My memory isn't what it used to be, but wasn't there a FAQ on this many years ago regarding a sticking/failing parking brake light switch!?..

TypeRod

I will check today when I get home from work. Might be hard to tell if the leak is inside the vehicle by the pedals, b/c a couple of years ago I had to replace my clutch MC, and that was leaking into the inside of the car. I'll check for leaks at each caliper and any part of the hard lines. I will mention that I when I started the car when I left work yesterday evening, the car felt a bit weird, like possibly a caliper was stuck/dragging, but I couldn't say for sure what it was. The light is already on, b/c the e-brake is pulled up, but when I lower the e-brake the light doesn't turn off. It does turn off when I brake and comes back on immediately after I release the brake pedal. But when the engine bay starts to get warm and up to operating temp, the issue goes away.

I changed the float b/c some said its possibly saturated and will stick, giving a false low brake fluid reading. After I changed it this past October, I havent had this issue pop up until last night. This "BRAKE" light staying on issue until engine is warmed up has been going on for years, but the only new variable is the actual low fluid. My fluid is kinda dirty, it has the greenish-brown filth floating around in the reservoir, some gets caught in the plastic filter/screen. I don't think that stuff will ever get fully flushed out and will never stop showing up.

Thanks for taking the time to post up those pics of the service manual! much appreciated!

Yeah, I did the same thing for all these years. I'll have to keep an eye on the fluid level since I've never seen it actually get low before.

I will look into that, thanks!

zrxdarryl

My 01 CRV did this on the really cold days once or twice last year. Changed the nasty fluid when I did a brake job which seemed to help.

It got down to 17 degrees here this morning - had the brake light on for about half of my 25 mile ride to work. Parking brake wasn't sticking, fully released.
No leaks anywhere that I could see.

DC2-ProdUcTiOnS

iTrader: (2)

Every time I have had this issue it has been bitterly cold. Once warm goes away, def never saw in Summer months.

That would be a diff story.

kingkau

Same my 2000 LS had the Brake light on too when its cold. It goes off after the engine warms up. Also top off the fluid too. I did that and it did helped.

TypeRod

Thanks all! I left work today and it was bout 23 deg. F. The issue didn't show up. I checked the bleed screws on each caliper and they were dry, I didn't jack the car up and take off the wheels, I just took a flashlight and gave it a once over. I checked under the dash and took a quick look for any fluid runs down the firewall and did see anything. I did see some left over staining from when the clutch MC was bleeding fluid done the interior firewall, but nothing from the brake pedal upper area. Fluid level looks to be the same as I left it yesterday. I'll just keep an eye on it for now. If I lose fluid again, I'll just change out the brake MC, since it will most likely be the culprit of the fluid loss. Thanks to all for your input and suggestions!

d=f20c1

iTrader: (1)

Does your horn work? If i remember correctly, when the horn fuse blows, it causes the brake light to stay on.

Just a thought. GL!

PeterVSays

my moms 2000 crv does the same thing on cold starts and days in norcal. after driving for a bit it does away.

TypeRod

Yes horn works. Thanks for the suggestion though! Hasn't happened since that day, but I'm still monitoring it.

98r860

You need to go under and look where your pedals are. Look at the brake pedal switch where it touches the brake pedal itself. There may be a missing rubber plug. The rubber plug engages with the switch to turn off your brake lights.

RTW DC2R

Hes not talking about the brake lights (tail lights). Hes talking about the "BRAKE" indicator on the gauge cluster, ie when the E-brake is engaged.

B16EJ

To the OP, I know what the problem is and its a very simple fix. Honda had a service bulletin years back to fix this issue as it happens to all integras with high mileage during cold weather.

You can either pop off the master cylinder cap and clean the float and the cap assembly, which will be filled with dirt and grit most likely, or just purchase a new cap and float assembly from Honda, it was only 14$ cdn.

I ended up cleaning mine up while waiting for the new float assembly and my cluster brake light never ever came back on again during cold startups. I never even bothered putting in the new assembly I'm just holding onto in case I need it in the future.

I took the whole cap/float assembly out and washed everything up nice in a container with a small amount of dish soap, dried it and re installed and I've never had an issue since.

I'm almost 100% certain this will work for you, it's a pretty common well known issue for the old timers such as myself lol. Best of luck I hope this fixes your issue.

98r860

My bad! I was in a hurry and thought I was on the right track when giving my thoughts.. my apologies!

I'm thinking that the circuit completes through the emergency brake handle switch and the float-level in the Master Cylinder. I suspect that the float-level is the culprit like B16EJ said.

Tom_Chooch

iTrader: (1)

This! I was just looking through service bulletins on the Acura iN network (dealer service network) and saw this bulletin. Very common fix on the older cars, especially if your fluid level is good.

TypeRod

Thanks for the help! I did replace the float a few months ago. And the incident did not reoccur until my original post in this thread. I can't remember exactly if I replaced the cap of the brake master cyl. reservoir or if it was the cap on the clutch master cyl. reservoir. B

But either way I'm keeping an eye on it, b/c the fluid was pretty low. If it gets low again, I'm going just to replace brake master cylinder, which all data seems to be point in that direction since I can't see any leaks at any of the calipers or in the engine bay under the brake master cylinder.

Thanks!

94eg!

iTrader: (2)

Fluid gets low because....
A - There is a leak
B - Your pads have worn down

For the leak, don't just start replacing things cause it probably wont solve your problem. Get under the car and look for fluid. Check the backside of your calipers (where the piston is). Check both ends of all your brake hoses. Check the ABS unit. Check the connecting joint on the firewall. Get in the foot-well and look for fluid by the brake pedal pushrod. Fluid will not leak into the booster and magically disappear. It's nasty stuff and you will find it if it's leaking.

For worn pads, topping off the reservior will fix the light. If it comes back on again soon after, it's most likely a leak.

If you don't have a leak, and you've topped off the master, and you've cleaned/replaced the float, then...... Check the parking brake handle switch. It's underneath the e-brake console cover (or armrest). It's just a crappy dip switch that grounds out to the chassis when the e-brake is lifted. If yours is sticky, it may not be popping out when you put the handle down. Then as the chassis heats up from the exhaust pipe, it might start completing the circuit which will cause the light to come on.

TypeRod

Thanks for the info!

sr-71

-This.

-Unfortunately sometimes people also confuse this issue with a faulty/worn master and replace the master for nothing.

So OP first thing I would do in such a situation before spending money on parts, if you haven't found any leaks, would be to clean the cap, float and filter and reservoir toroughly first and bleed the whole system because your brake oil seems like past due to start with and that may very well be at the root of the issue you are experiencing.

My guess is that with fresh brake oil, you won't see the level going down or the brake light coming on about until next time it's due for servicing again.

As you probably know, humidity builds up in the system over time and in the long run it becomes trapped inside with brake fluid which give you somewhat of a false reading if you consider only fluid level, when brake oil is really old. Plus as your oil degrades, it's boiling point/resistance to heat goes down and a small part of it evaporates along with it's constantly growing water content as it slowly loses it's proprieties...which might get that light on or trick you into thinking that there is a leak in your system when in fact, there isn't. In my experience, topping off the oil usually works for a while and will only be a temporary solution until enough contaminated fluid evaporates again due to heat or until you bleed your brakes as far as the light is concerned, especially if you don't track your car.

If you track your car hard or go for a full track day in pretty hot conditions or where the car rests for less than an hour between sessions for instance, it might have lost a bit of brake fluid by the end of the day and that's normal.

If you occasionally track your car or just do one or 2 short sessions and you get the light or find yourself having to top off the oil after just a few sessions to get that brake light off, you might want to replace the fluid and bleed the whole system if the light comes on, even if the fluid still looks good to the naked eye or hasen't been in for a long time.

TypeRod

Thanks for the suggestion SR! I wish I felt comfortable doing a brake fluid flush myself, bc I would completely flush all the lines till I didn't see any more filth floating around in the brake MC reservoir. I had it flushed about 1.5 years ago, and only have driven about 10k since then, but when my buddy did the flush he didn't flush it well enough to the point where my OCD wasnt' bothered by it, lol.

I don't track the car in any way, its has been and always will be my daily driver.

I'm going to really have to consider some of the offers Ive been getting for my R, she deserves better than what I can do for her now.

TypeRod

Could it be possible that my brake pads get so worn that the fluid gets low enough to trigger the "BRAKE" light?

94eg!

iTrader: (2)

Yes. That's why I said...

"For worn pads, topping off the reservoir will fix the light."

But if it comes back on within a short period of time, there is another reason for the level being low (leak).

TypeRod

I have had worn pads before on this car, but never did the light ever come on due to low level brake fluid. Good to know, thanks.