ABS Light/Malfunction

[marcdh]

Hey guys - a problem with my project 1994 mx3,

The abs light is on constantly, and the ABS does not appear to work.

I've tried to pull codes by shorting TBS to GND in the usual diagnostics port, is this meant to make the ABS light show codes? Mine just stays on solid. Any thoughts?

club323f guys found me this:

To access the codes on 1992-98 models, the following are required: Mazda System Selector Switch 49-BO19-9A0 and Self-Diagnosis Checker 49-HO18-9A1 or a scan tool. If a scan tool is used, be sure it is capable of pulling codes from ABS systems. Not all scan tools have this ability.

1.

Connect the Mazda system selector switch and the self-diagnosis checker or a scan tool to the underhood data link connector and to a ground. Set the select switch on the checker to A and the system selector knob to position 3. On scan tools, access the ABS menu. Follow the menu on the scan tool to access the codes. If any codes are present it will display the code number and the corresponding circuit or component.
2.

Turn the ignition switch ONand observe the checker display. Initially, code 88 should appear. If code 88 does not appear check the connections between the checker and the selector. After code 88 appears, watch for and record any other trouble codes.
3.

After the proper repairs are made, the codes must be erased by doing the following:
1.

At the data link connector under the hood, connect the TBS terminal to GND.
2.

Turn the ignition switch to the ON position.
3.

Output all of the memorized trouble codes.
4.

After the first trouble code repeats itself, depress the brake pedal 10 times at intervals of less than 1 second. This will clear all trouble codes.

Can't I replicate this using LED and shorting with wire?

many thanks,
Marc

[Aston Wards]

I've never tried to get codes from the ABS before, but with the auto tranny codes, you need to reset the ecu FIRST ie, take off the negative battery cable, depress/pump the brake, jump the diagnostic terminals, switch on the ignition...., read codes.

If this still doesn't work, try/borrow a new ABS computer (under the passenger seat)...., or disconnect the bulb and try not to crash

[hgallegos915]

Mine has been on since i first got it.. then one day the abs unit was making a weird noise and wouldnt shut up.. i disconnected the abs module from the hanness.. car drives the same.. bleh abs.

[spoddy]

Hi

I am having the same problem at the moment marcdh, I got ball joints replaced on my az3, its got ABS which is rare as I have a mate in Cork who has converted his drum rear brakes.

Anyway the mechanic tested the ohms and voltage while spinning the wheel on each front ABS sensor and only the passenger one was registering any reading. I am trying to source one as it has a two bolt connector to the wheel.
I bought one off ebay which is for the left to see if I can turn it around, I did see some on a german web site which look more suited.

How did you get it fixed? Does the mazda 323f model have the same abs sensors?
I live outside Belfast, in Co Armagh, so pretty close to you, and my az3 is black as well.
Good to find another mx3 fan locally.

All the best
Ronnie

[marcdh]

Here's a quick how to pull ABS codes for general reference. Do this if your ABS (car skidding) light wont go away.

1) Connect a jumper wire in the diagnostics box from TBS(Test Brake System) to GND terminals.
2) Connect LED+ to FBS (Fault:Braking System) terminal and LED- to a GND, there are 2 GNDs on the diagnostics box, or any ground will do.
3) Turn key to ON

Note
You are meant to use an analog voltmeter, but I found it lit an LED sufficiently.
Long flashes = tens
Short flashes = ones

Code List
11 Right front wheel speed sensor or rotor
12 Left front wheel speed sensor or rotor
13 Right rear wheel speed sensor or rotor
14 Left rear wheel speed sensor or rotor
15 Wheel speed sensor
22 Hydraulic unit harness
51 Fail-safe relay
53 Motor or motor relay
61 ABS control unit

My problem turned out to be the actual ABS motor and a sensor. Have you cleaned the toothed rotor?
Regarding using the opposite side sensor I have done this successfully on my front right

I got you PM so I'll write back soon

[wytbishop]

Anybody know where to get an ABS sensor for cheap? I wrecked one changing my rear spindles. Most places want $275ish. Rockauto wants $175ish. I would like to pay a lot less than that. Everyone I try to pull off a used car disintegrates.

[marcdh]

I have a used rear one Charlie, I haven't checked it's in spec though. It looks decent, but I'll have to dig out the multimeter.

[wytbishop]

that's a long way to go for a little sensor...lol. I can't remember if I need left or right, but it's a rear that I need.

[spoddy]

Thanks for the info, hopefully only the sensor as it was not registering any current through multimeter.
Can you clean them, or fix them in any way what are they exactly a magnet of some kind?

Cheers

[wytbishop]

It's a Hall Effect Sensor. The Hall Effect is related to the interaction of electic and magnetic fields. When the tone ring interrupts the magnetic field created by the magnet that extends from the sensor, a votage difference is generated and detected in the sensor. So every time one of the teeth of the tone ring approches the magnet the sensor senses this votage difference and sends a signal to the ECU. Then when the tooth passes the voltage difference ceases and the sensor's signal stops. The frequency of the signals from the sensor tells the ECU how fast each wheel is turning. If all four wheels are not turning at the same speed the ECU tells the ABS brain to release the brakes until all four speeds are the same again and then reapplies....and off and on and off and on until all four wheels are in sync again.

[WhiteFinish]

It's a Hall Effect Sensor. The Hall Effect is related to the interaction of electic and magnetic fields. When the tone ring interrupts the magnetic field created by the magnet that extends from the sensor, a votage difference is generated and detected in the sensor. So every time one of the teeth of the tone ring approches the magnet the sensor senses this votage difference and sends a signal to the ECU. Then when the tooth passes the voltage difference ceases and the sensor's signal stops. The frequency of the signals from the sensor tells the ECU how fast each wheel is turning. If all four wheels are not turning at the same speed the ECU tells the ABS brain to release the brakes until all four speeds are the same again and then reapplies....and off and on and off and on until all four wheels are in sync again.

puf puf... **dust of the old topic**

I have a complete rear spindle. The problem with our rear abs sensors is they get stuck in the rear spindle.

Who has a good idea to get it out??

Could I use a grinder to cut the rest of the spindle out of the way or would the heat/vibrations kill the sensor?