Abs kicks in early

[Big Mark]

My abs seems to kick in too early, is this normal or could there be a possible fault?

 

My car has UK brakes fitted and other than a very slight fluid leak due to perishing grommets between the fluid reservoir and master cylinder there is no other visible issues.

[skippyboyo1]

It's winter and slippy?

[Big Mark]

It's done it since I bought the car in summer, I've just never got around to looking into it until now.

[dr_jekyll]

what size tyre do you have? if the rolling radius arnt mached fron to rear the ecu will see the underrotation of a smaller radius as lock and intervein earlyer

[Big Mark]

Running the factory 17 inch wheels and I'm sure factory spec tyre sizes.

[dr_jekyll]

be worth checking the sizes

[Big Mark]

235/45/17 Fronts and 255/40/17 rears

[dr_jekyll]

Thats rite,

[Big Mark]

Exactly. I've always been able to judge my breaking and brake late without locking up or abs kicking in but not so with my supra.

Edited November 25, 2012 by Big Mark (see edit history)

[dr_jekyll]

Exactly. I've always been able to judge my breaking and brake late without locking up or abs kicking in but not so with my supra.

 

abs is for girls anyway, just remove it

[jonc]

Sensor problem?

Mine did it after I had completed a load of work on the front end . No error codes stored but I found that I had not fitted my nearside front sensor correctly:(.

 

Could be the sensor or some crap on one of the toothed rings.

 

You quite easily see if you have any ABS fault code stored with basic tools and using procedures stated in the repair manuals:-

 

 

ABS Light Diagnostics

1) Turn ignition on. ABS light should come on then go out

after 3 seconds. If light does not come on, check fuse, bulb, and

wiring harness.

2) With ignition on, unplug short connector from DLC1. See

Fig. 5. Using a jumper wire, jumper check connector terminals Tc and

E1 of DLC1 or DLC2. If system is functioning properly, ABS light will

flash 2 times per second. If a malfunction is detected, 4 seconds will

elapse, then ABS light will begin flashing 2-digit DTC.

3) ABS light will flash first digit of DTC, followed by a 1.

5-second pause, then second digit of DTC. If 2 or more DTCs are

stored, a 2.5-second pause will separate DTCs. After all DTCs are

flashed, there will be a 4-second pause, then all DTCs will repeat.

For code definitions, see DTC DEFINITIONS.

4) After replacing or repairing malfunctioning component,

clear DTCs. If battery cable was disconnected during repairs, all DTCs

will be erased. If battery cable was not disconnected during repairs,

see CLEARING DTCS.

Fig. 5: Identifying Data Link Connector Terminals

Courtesy of Toyota Motor Sales, U.S.A., Inc.

DTC DEFINITIONS

NOTE: ABS light displays DTCs. Each DTC will light a warning light

when a problem occurs. Supra uses 3 warning lights; ABS

light, TRAC light and TRAC OFF light. After each Code number

the light sequence for that code will be shown. For example;

Code 11 - On/Off/On, (On/Off/On sequence means ABS light On,

TRAC light Off and TRAC OFF light On).

Check suspect components in given order. Unless otherwise

noted, checks consist mainly of visual inspection and continuity

checks. Go to appropriate DTC chart, see CIRCUIT TESTS.

Code 11 - On/Off/On

Open or short in solenoid relay circuit. Check actuator

wiring harness, solenoid relay, solenoid relay wiring harness, and

solenoid relay connector.

Code 12 - On/Off/On

Short to voltage in solenoid relay circuit. Check actuator

wiring harness, solenoid relay, solenoid relay wiring harness, and

solenoid relay connector.

Code 13 - On/Off/On

Open or short in pump motor relay circuit. Check actuator

wiring harness, pump motor relay, wiring harness, and pump motor

connector.

Code 14 - On/Off/On

Short to voltage in pump motor relay circuit. Check actuator

wiring harness, pump motor relay, wiring harness and pump motor

connector.

Code 15 - On/On/On

Open or short in TRAC solenoid relay.

Code 16 - On/Off/On

Short to voltage in TRAC solenoid relay circuit.

Code 17 - On/On/Off

Open or short in TRAC motor relay circuit.

Code 18 - Off/On/On

Short to voltage in TRAC motor relay circuit.

Code 21 - On/Off/On

Open or short circuit in solenoid for right front wheel.

Check actuator solenoid, wiring harness, and connector.

Code 22 - On/Off/On

Open or short circuit in solenoid for left front wheel. Check

actuator solenoid, wiring harness, and connector.

Code 23 - On/Off/On

Open or short circuit in solenoid for right rear wheel. Check

actuator solenoid, wiring harness, and connector.

Code 24 - On/Off/On

Open or short circuit in solenoid for left rear wheel. Check

actuator solenoid, wiring harness, and connector.

Code 25 - On/On/On

Open or short in TRAC SMC actuator solenoid circuit.

Code 27 - On/On/On

Open or short in TRAC SRC actuator solenoid circuit.

Code 31 - On/Off/On

Malfunction of right front wheel speed sensor signal. Check

speed sensor, sensor rotor, wiring harness, and connector.

Code 32 - On/Off/On

Malfunction of left front wheel speed sensor signal. Check

speed sensor, sensor rotor, wiring harness, and connector.

Code 33 - On/Off/On

Malfunction of speed sensor signal for right rear wheel.

Check speed sensor, sensor rotor, wiring harness, and connector.

Code 34 - On/Off/On

Malfunction of speed sensor signal for left rear wheel. Check

speed sensor, sensor rotor, wiring harness, and connector.

Code 35 - On/Off/On

Open in left front wheel or right rear speed sensor circuit.

Check speed sensor, sensor rotor, wiring harness, and connector.

Code 36 - On/Off/On

Open in right front wheel or left rear speed sensor circuit.

Check speed sensor, sensor rotor, wiring harness, and connector.

Code 41 - On/Off/On

Battery voltage is abnormally high or low. Check battery and

voltage regulator.

Code 44 - On/Off/Off

Open or short in lateral acceleration sensor. Check sensor,

wiring harness, and connector.

Code 51 - On/Off/On

Actuator pump motor is locked or pump motor circuit is open.

Check pump motor, pump motor relay, vehicle battery, actuator wiring

harness, connectors, actuator pump motor circuit, and actuator ground

bolt.

Code 55 - Off/On/On

Brake fluid level is low in reservoir.

Code 58 - Off/On/On

Open circuit in TRAC pump motor circuit.

Code 61 - Off/On/On

Abnormal TRAC ECU communication.

Code 62 - On/On/On

Wheel speed sensor malfunction.

ABS Light Always On

Malfunction of ABS ECU. Inspect ABS ECU connector for

security and undamaged terminals. If connector is okay, replace ABS

ECU.

 

A bit long winded but hope this helps

[Big Mark]

Thanks for that! I've printed it off so will have to hand when I give the car the once over.

 

One quick question.. What should my warning lights be?

 

To the left of steering wheel I have Seatbelt warning, blank, battery, one engine warning light, lights and to the right of the steering wheel I have engine warning, blank, oil level warning, oil temp warning.

 

I get the feeling the two blank one shouldn't be.

 

Sorry for the pics, taken on a very old phone...

[jonc]

From the left hand photo the blanks are:-

Airbag warning to the left of the battery which comes on when you turn on the ignition then goes off after a few seconds.

Door open warning between seatbelt and battery which obviously comes on when a door,boot,bonnet is open

 

From the right hand photo the blanks are:

ABS light above the engine management light which does the same as the airbag light. It comes on for a few seconds when you turn the ignition on then goes out

 

That is off the top of my head but I will check tomorrow when I go to work

[Swampy442]

I need to ask, how do you know its kicking in early? You shouldnt experience ABS kicking unless youre about to impact some part of the scenery. Unless youre Jason Plato...

[Big Mark]

I need to ask, how do you know its kicking in early? You shouldnt experience ABS kicking unless youre about to impact some part of the scenery. Unless youre Jason Plato...

 

I can feel it kicking in and I know that I'm not breaking hard enough for it to be needed.

[Chris Wilson]

Either an ABS sensor / control ECU / unit issue, *OR* you have a sticking brake and it's already braking that tyre X%. When you brake the effort increases disproportionately to the other tyres and a wheel lock or partial lock occurs and the ABS triggers. Is a brake binding???

 

As an aside cheap grooved, "drilled" or otherwise pratted about with discs from the far east, seemingly made from recycled dustbin lids and woks, rust so fast in wet weather that they have a ludicrously thick oxide coating that causes bind until it is rubbed clean again.

[Swampy442]

As an aside cheap grooved, "drilled" or otherwise pratted about with discs from the far east, seemingly made from recycled dustbin lids and woks, rust so fast in wet weather that they have a ludicrously thick oxide coating that causes bind until it is rubbed clean again.

 

Lol! But they have holes in them, race cars have holes in their discs, must be the same....

[Big Mark]

Stock discs so it's not that. I'm planning on getting cleaning and painting the calipers as well as fitting braided brake lines over xmas so will give everything a thorough check then. Thanks for the advice guys.