Troubleshooting: "ABS" and "Brake" dash lights (1 Viewer)

[hatchethead]

Tonight, driving home from the Costco, I noticed that my ABS and BRAKE dash lights were on. I don't think I've ever pulled the emergency break in the 6 months I've owned my 2004 100-series, and I certainly didn't mess with it today. The only thing that's happened near the ABS or brake system is new tires put on by Americas Tires on Thursday. I want to bring my rig to Yosemite on Wednesday, so I'm working hard to track down the source of the apparent problem.

While driving, my breaks worked fine. I search the forums here for any previous conversations that might explain what I'm experiencing. I've found a couple that suggest the brake pump might be on the fritz. Another excellent thread explained how to troubleshoot the level of brake fluid. I'll go through those steps in the morning. A few minutes ago, I took the truck around the block to test the breaks. Nothing had changed and the brakes worked fine. I decided to pump the breaks. At about pump number 12, an alarm started to sound. After a few moments, it stopped.

I'm hoping that all I need to do is add some brake fluid. Is there something else I should be investigating?

Thanks for your guidance and suggestions.

-- Jason

 

[badlander]

Check brake fluid level level and condition (color).
Check tire air pressures. If one is low it may trigger an ABS code due to uneven tire speeds caused by a smaller diameter tire.

ABS codes may be accessed using a jumper wire at a small covered box near the top of the passenger side inner front fender in the engine compartment. When activated the codes are read via flashing light code numbers on the dash display ABS lights.
The procedure is detailed in the FSM.

Good luck.

 

[hatchethead]

Check brake fluid level level and condition (color).
Check tire air pressures. If one is low it may trigger an ABS code due to uneven tire speeds caused by a smaller diameter tire.

ABS codes may be accessed using a jumper wire at a small covered box near the top of the passenger side inner front fender in the engine compartment. When activated the codes are read via flashing light code numbers on the dash display ABS lights.
The procedure is detailed in the FSM.

Good luck.

Thanks! I’ll try this out today!

 

[hatchethead]

Following up on my original post...

(1) I leveled my rig and pumped the break 40x with the power off.
(2) Checking the reservoir of brake fluid, I verified that it was waaaaay too full. [pic forthcoming]
(3) Removed excess brake fluid using a syringe. Verified that the fluid's color is good. [pic forthcoming]
(4) Turned the ignition "on"; the pump started working and sounded good.
(5) Looking at the FSM, saw that connecting a jumper between Tc and E1 (inside hood on passenger side) would give error codes through flashing of icons on dashboard. This is what I saw: ABS light ("34"), check engine light was solid on, 2nd start light was blinking evenly, Cruise light was blinking evenly, Airbag light was blinking evenly, A/T oil temp light was on solid, and the battery icon was on solid.
(6) Looking at online references, the ABS of "34" indicated something was wrong with the left (drive side) rear speed sensor.
(7) I then connected my cable to my installation of tech stream, and I got a bunch of information, some of which seemed consistent with the ABS error.
(8) I also noted that my two right tires were filled to 35 psi and my two left tires were filled to 32 psi. (This must have been an error on the part of the Americas Tire that installed my new tires last week.). I aired up the two left tires to 35 psi.
(9) For for a short drive. The dashboard lights were off and the breaks worked fine.
(10) When I returned, I rechecked the system with my Techstream installation, and I saw the same errors. Do I need to reset the system to clear the original errors?

Jason

 

[badlander]

Good work. Sounds like you are on the right track.
Yes you need to erase that code from the system and then go for another test drive to see if it pops up again.
Also, it might be a good idea to check the speed sensor wire and connector plugs next. Unlikely, but maybe you hit some road debris and damaged something back there......worth taking a look.