ABS/Brake light issue

[precisionmike]

Hello All,

We have a 2007 Ram 5.7 that has an ABS/Brake light that comes on and goes off intermittently. O'Riellys pulled a code that said the brake fluid was low, but it is not. This is the only code they could find.

Is it possible the brake fluid level sensor is bad? I have a a meter, can I test it?

From the research I have done, I understand that this issue is most commonly an abs speed sensor, of which there are one on each front hub and on in the rear diff. I didn't want to start replacing those if I am not getting that code.

Any advice would be greatly appreciated. Thanks, Mike

 

[Rlaf75]

You say intermittently. Do they come on when you're braking or randomly while driving? Do you notice any vibrating or faint grinding or buzzing noise when you're braking?

 

[blackbeautyhemi]

Yea it's probably the brake fluid level sensor. I just had to replace the reservoir on my truck cause of the light coming on and off repeatedly. Hasn't come on since.

 

[precisionmike]

You say intermittently. Do they come on when you're braking or randomly while driving? Do you notice any vibrating or faint grinding or buzzing noise when you're braking?

There appears to be no noise, it is completely random and it does not seem to be triggered by bumps. I did a front brake job about 6 months ago and topped the fluid then. The lights were coming on prior to the brake job and since, no change.

Thanks again.

 

[blackbeautyhemi]

When I changed my reservoir I emptied the old one and it was all sludged up around the floating sensor and it wouldn't move til I blasted it with brake cleaner then it free'd up some.

 

[precisionmike]

So I unplugged the harness at the brake fluid reservoir. Been driving the truck for the past several days and the lights have stayed on, never going off. It would normally go on/off about every 3-5 miles or so.

At this point I think i have determined that the float or sensor are bad.

I don't need a light to tell me that the fluid is low. Has anyone measured for resistance on the sensor? My guess is that it is normally closed when at the proper level, opened when low. Is so, I should be able to run a jumper between the 2 pins and be good. Thoughts?

 

[blackbeautyhemi]

I tried running a wire from side to side on the plug and it didn't work. So I just ordered a new reservoir cause it was only $50. You could try taking the fluid and cleaning the gunk inside that's probably built up around the float like I said in the previous post

 

[precisionmike]

I tried running a wire from side to side on the plug and it didn't work. So I just ordered a new reservoir cause it was only $50. You could try taking the fluid and cleaning the gunk inside that's probably built up around the float like I said in the previous post

So how hard was it to swap? Would I have to bleed the system?
Thanks

 

[blackbeautyhemi]

Nope as long as you leave the fluid in it you won't have to bleed it. Leave the cap on the reservoir, take out the bolt that holds it on to the master cylinder, push the reservoir towards the passenger side fender and it'll pull up out, leaving the cap on helps keep the fluid from pouring outta the bottom of the reservoir. I just put a drain pan under the master cylinder to catch any fluid that did drip. Once it's out the fluid still in the master cylinder keeps air from getting in the line. The new one just pops down in the master cylinder and the bolt goes back in. Pour in new brake fluid and spray off the master cylinder with brake cleaner to clean it up. Took like 30 minutes to do.

 

[usaf2006]

My lights also come on intermittently as yours do. When I flushed my truck I attempted to clean the sensor off and the lights didn't come on for a good three months. They're back at it now though.

 

[precisionmike]

Good to know, thanks fellas.

 

[precisionmike]

So I am trying to remove the reservoir. I only see one bolt which I have removed. It is loose but will not come off. What am I missing? ....googling now too. thanks

 

[precisionmike]

I have it removed. It is full of crud. I am going to try to clean it and see if it works. If not, I will replace. No one has it in stock, 3 days to get. Thanks again

 

[blackbeautyhemi]

Yea I didn't realize mine was that cruded up before I bought a new one or I would've tried that first.. Worth a shot if you can get it all out.