Brake light on - Where do I start?

[Brownfamily]

I am having this issue where the brake light on the dash is on. I assume it is either low fluid, air in lines, or a vacuum issue. I will start with checking the fluid and bleeding. If it is a vacuum issue i guess i will take the risky ride down the hill to a shop. Is my logic correct?

[Oz]

Could be that your fluid is low.  Yes, check that first.  If you have low fluid pressure due to needing to bleed the brakes, you'd notice it in the brake pedal.  It would be mushy with a lack of stopping power.

Could also be just a wiring issue.

But, you're off on the right foot.  Check fluid level, bleed brakes if you don't know when they were bled last (even if you don't notice the low pedal pressure I mentioned).  It would be a good idea to bleed the entire system with all new fluid.  I had no idea when mine had been done last, so that's what I did and the old fluid looked like engine oil!

Message search "bleed brakes" for the correct process.

It would be a good idea to get the eManual from the store.  You can't really do repair and maintenance without it.  The old Dodge manuals are excellent.  Plus, you get a free, 1 yr membership upgrade which gets you tons more on appliances and bunch of other things in the Member Area as well as other benefits.

[Brownfamily]

Great. Well I did check fluid although really had to know how. Ugh is needed as you can't see inside due to the crazy location. Also there is a rubber casket contraption that makes it difficult to know how much to put in.

Haven't tried it yet as we are on a steep driveway/road. Fund out that the parking break has been disconnected even though that wouldn't do much good in an emergency.

My issue is that the breaking on this is so touchy. It's almost like they are on or off. Very hard to feather. Not sure if this is normal for these rigs or if I can do something.

I did try the test for calcium I found on this site whereas you put foot pressure on the break pedal then start the rv. It says the pedal should go down, but mine doesn't.  Not sure if that's a true test or what.

Anyhow if I can solve the wandering and break issue it will feel a lot safer on the road. 

Any tips?

[legomybago]

I did try the test for calcium I found on this site whereas you put foot pressure on the break pedal then start the rv.

Not sure what "calcium" test is..... Hm? , But what this tells you is if your vacuum boosters (power brakes) are working if your peddle moves down when you start the rig. Sounds like yours arent. Could be a number of things. Check and see if you have engine vacuum going into the booster, the check valves have been known to stick closed where the vacuum line plugs into the booster.


You need to fully bleed the system with fresh fluid

Sticky brakes can be loose wheel bearings, shoe adjustment issues, miss matched or contaminated brake shoes, drum out of round. Jack up the front end and make sure you dont have a hub assembly about to come flying off (shake the front tire/wheel, up down and side to side) make sure they are tight.

Bleed your brakes, and then work on your power brakes.

Some ideas for ya

[Brownfamily]

Thanks. Lots of work ahead. Not sure about the calcium word. Weird spell check i guess....should be vacuum.

[Oz]

As I said before and was reiterated, start by bleeding the brake system completely, then if there's no change, move on to the next thing.

The master cylinder is in a tough place to see.  Actually, unless you're a snake, you can't see how much is in it.  And I know about how the rubber thing in the cap gets all bent out of shape.

You could cut an access door in the floor of your cab above it which would greatly simplify things.  It's been done.

In order to refill mine, I used a squeeze sports bottle just like the kind they use in football, with the long bent tube.

The one chamber is for the font brakes, and the other is for the rear.  The rear one is a lot smaller so you have to be very careful not to bleed too much at once.  Like 6 pumps at the most before refilling. 
You can use your finger or a bent straw or anything which you can stick over the top and dip into the reservoirs to see how full they are.

A vacuum pump/brake bleeder is a major help in getting the job done.

[Brownfamily]

great. Yea i really need to check out the brake vacuum issue. I also am looking to remove the front drums and take a look there too.

I think the vacuum issue is going to be the hardest to resolve. I dont have any real large truck repair places close to me and hate to think of the money they will charge.

Maybe its a simple connection at the motor so will have to research to see where that is.

[Bennett77]

Had this problem with my 77, brake light would come on. My system works from the power steering system. All hydraulic, after morphing into an octopus and refilling the brake fluid following the direction in the Dodge service manual, turning the steering and applying the brakes, bleeding the system and adding power steering fluid, repeating and repeating the brake system is good. At first all I could see is dollar signs.

[Oz]

Goes back to ensuring the system is free of air and fluid is full.  On the brownfamily's RV, the power steering isn't involved so it's just bleeding the brake system.