4runners0206

Hi,

My '02 4Runner is showing and sounding a brake alarm intermittently. When this happens, the the dash lights up but the CEL does not. I also get the high pitched warning sound.

This has occurred about 4 or 5 times. Each time it has turned off on its own after a few to several minutes of driving. Each time it has happened, I have not noticed any issue with the braking system. It seems to be functioning as it always does. I do, however, drive with my hand on the E-brake lever just in case the brakes fail.

So far, my efforts to address the problem have been:

Cleaned off the battery terminals. They had some corrosion on them but it didn't appear to be too bad.

Checked the brake fluid level in the master cylinder--it was right at the full line

Cleaned the passenger and rear passenger ABS sensors. The rear had some dirt and grease on it, but it's clean now. Front was clean. I plan to clean both driver side sensors later today.

Since I don't have an ODBII reader, I haven't been able to get the codes when the alarm is sounding. Went to AutoZone and they said they couldn't read brake codes with their reader. They also said I would have to get one of their $100 readers in order to do this.

My questions:
Has anyone else had this similar problem? If so, I'd be interested in hearing about the solution.
Is there a lower cost ODBII reader that I can get online or use with a smart phone that will read brake codes?

If the codes point to a sensor, I can probably change it out myself. At 204K miles, I'm hoping it's not the master cylinder. If feasible, I'd like to keep this truck. It's been great and the motor still runs strong.

Any advice or ideas would be greatly appreciated.

Thanks!

Bigtooona

Yeah, that's your master cylinder going. Dealer quoted me $3k for the part alone, I bought a rebuild unit off ebay and so far it's doing alright. Still gives a squeal every now and then but no alarms or "brakes dropping out" feel.

http://www.toyota-4runner.org/3rd-ge...tup-doing.html

4runners0206

Thanks BT! Today I finished checking my ABS sensors and found that the rear driver's side sensor was covered with differential oil.

Could this be the cause of the warnings I've been getting?

I cleaned the sensor and the hole it sits in. There wasn't a ton of oil but it was there nonetheless. Could be the reason I was getting the warnings?

Thanks again

wyoming9

iTrader: (1)

If you really drive with your hand on the E-Brake Handle have you thought it might be from movement in the handle causing the E brake light circuit to close ??

Bigtooona

I can't say for sure, but if it was your ABS you'd probably be showing a code with a standard reader. I had one come up as well and replaced one of the sensors (can't recall exactly which one, but fairly certain one of the rear ones) and that code went away but didn't fix the issue.

I had the most issues when the ambient temp was sub-freezing, not sure if you're seeing the same.

TheDurk

The warning buzzer is probably an issue with the hydraulic brake booster.

http://www.teamtoyota4x4.org/archivi...br/hbb/ovi.pdf

You can read and clear ABS codes with a stinkin' paper clip, no reader needed.

http://www.teamtoyota4x4.org/archivi...bdb/preche.pdf

Where it says use your SST, substitute your stinkin' paper clip.

When in doubt, RTFM. Find it here:

http://www.teamtoyota4x4.org/archivi...s/contents.htm