Long story short, I had the typical alarm and dash light up in my 2002 100 Series with 155K miles. The work was done by a toyota specialist garage that I've been going to for years. They replaced the master cylinder with a brand new unit and are still getting the alarm & dash light up. They went so far as to redo the master cylinder again (new, new unit), along with a long litany of checks and tests to figure out what the heck is going on still. As they've done the work, the codes have changed a couple times...I took the car back yesterday and am going to go to a repair parts store to get a current set. I have confirmed the Abs is not activating. Welcome any thoughts on what this could be or things I should investigate.
Help! Mechanic replaced Master Cylinder but still getting buzzer and dash light up (1 Viewer)
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They replaced the master cylinder with a brand new unit and are still getting the alarm & dash light up.
Do you mean the MC only, or the entire pump/accumulator/MC unit ($1300+ bucks at a dealer)?
Do you mean the MC only, or the entire pump/accumulator/MC unit ($1300+ bucks at a dealer)?
To clarify, why they replace the mater cylinder… meaning just the hydraulic part. This system has a ecm , accumulator and ABS control valves internal to this entire unit. There is an ECU, master cylinder, accumulator, and pump .. this all is integral unit but some parts of it are changeable. The untire unit booster / controller/ mater cylinder/ is an expensive part all as one unit.
Now the why comes in … what lead you to needing it looked at the 1st time?
Lights in dash, pedal go to the floor, noise when pedal is pumped, pedal fading
Under your foot holding the brakes?
I have replaced the pump
Motors before, on different Toyotas 4Runners. And repaired a 4Runner ABS / Trac lamp. That was a rat had eaten a wire bundle and cut a ground wire and throwing a ABS / Trac lamp.
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- #4
I followed the direction of the shop who said the master cylinder was locked up. I brought it in b/c of the buzzer and lights on the dash. Funny thing was that I didn't have any noticeable brake issues at the time...everything was normal except for the lights.
I am really curious about the wire bundle...i've heard that before and suspect it could be the issue. How do I diagnose? I brought it up to the shop too and they said they examined it and couldn't find anything wrong...
Well codes … that points you in the direction … if it’s electrical . Which circuit has an issue.
Haven’t seen the buzzer issues before. New to land cruisers but lots of 4Runners use this booster system.
Lights in dash that indicate some
Electrical / code should be present.
Now what one ? Then have to determine what can cause said code, a mechanical thing or electronic thing to put it simple.
Code points to the area of the issue, not necessarily the part that has failed.
Just an FYI toya dealers replace entire booster assy
Includes master cylinder. How many miles on yours ?
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- #7
158K. Just went to auto parts store and no codes coming back....
Parts stores carry Ecm for engine codes. Most of their scanners only do engine / emission.
If your ABS light or Traction control light depends on year, you have a ABS Code normally,
Layer models like for instance my 02 4Runner trigger a Traction code it sets off the Chexk
Engine lamp and also if an engine emissions code setup off my ABS / Trac lamp. Warning lamps came in for an O2 sensor on my 02 4Runner.
So. No engine emission codes ok, step 1
Any warning lamps , brake red, or ABS and or Trac?
That requires a scanner to communicate to the ANS Trac if equipped ecm. As if and Airbag SRS light, requires a Scanner to talk in the protocol to SRS ecm.
I have a the scanner that communicates with most of the ECMs in a OBS2 vehicle all makes.
Cost me 600 a year to keep it updated
Programs Coded Keys ect on differ makes.
Most scanners at parts store only do Engine Emission ECM tho.
Now two ways to deal with ABS codes
Some
Older models can short a connector and flash a code like my 2002 Yota or use a computer with Toyota Tech steam with a uSB to OBD2 connector
Or buy a scanner Amazon ect to access more information through the OBD2 connector
Or pay a shop
Depending on year, it’s entirely possible to short a connector and flash a code .
Now , Alldata has online service manuals or download yota service manuals for your year coverage to guide you through code retrieval processes.
Hope it helps
I looked up diagnostic stuff for my 99... 2002 i bet is different in ways. I looks to short a two connectors TC and E1 to flash codes. The chart shows DTCs via Scanner and 2 digits codes for the flashing codes.
Which OBD do you use and do you which ones work or a 1998 LC?
Hello, I am not at the house shop, but it’s an Autel version and does wireless dongle to OBD2 connector and TMPS sensors.
Now I would check out to see if it supports the protocols and has software to check SRS, ABS, codes at a minimum plus ECM engine. Mine does a lot of ECMs on the bus for example Honda , toya , ect , cruise , key, SRS, ABS , Climate, Traction control, ect …
Hope that helps
99 year should support manual flash codes on the ABS I beleive , find OEM manual and look. The code references show two type of codes. One is OBD2 and the other is Manual code two digit flash.
Something like this
To follow up on ABS code retrieval Manaully WITHOUT a scanner.
See service manual Diagnostic / ABS troubleshooting can be downloads on the forum board.
Quick overview:
See pics, short a connector and count flashes ,see how to interpret flashes ..
See service manual Diagnostic / ABS troubleshooting can be downloads on the forum board.
Quick overview:
See pics, short a connector and count flashes ,see how to interpret flashes ..
