Disabling ABS

[SamoL]

Hi!

I've found out, that LC 100 has a multi program ABS, but ABS is fully turned off only when rear diff lock is engaged. It bothers me as I'm not able to brake efficiently on gravel. Did anyone figured how to disable ABS (except for the "pull the plug" method)? For me it would be great if ABS would be turned off when center diff lock is engaged. Where is the ABS computer and does anyone have a wiring diagram (I don't have a factory service manual - does anyone have it in electronic form?).

Regards

Samo

[100 TD]

I am very interested in the "LOGIC" for the control of the ABS (and other things) and would love to know the parameters that turn it on and off, ie. what is selected, what speed , what gear, what transfer position, locker diff selected or not (on models that have it) etc etc. I am soon( hopefully) to fit airlockers to my vehicle (no original elockers) and had intended switching the inputs to the combination meter or ECU if I can find them (there are so many SPARE wires and connectors everywhere) so that when I switch my diffs in it will use the original lights on the dash to indicate them. This however could cause confusion with the ABS etc. Any info on the system would be great.

[clownmidget]

Have you tried the method used for the 80-series? Engage CDL with dash switch, drive @ approx 42 mph for approx 100 meters, then disengage CDL with dash switch, ABS remains deactivated...

[SamoL]

On a 100-series ABS is not disabled, when CDL is engaged. It is only disabed when RDL is engaged. ABS on a 100-series is "smart" and it switches to a different program when CDL is engaged - if you ask me, this is bullsh... On what kind of road would you engage a CDL and need ABS?

Regards

Samo

[hoser]

Originally Posted by SamoL

On what kind of road would you engage a CDL and need ABS?

Some people like to have the CDL engaged on snow/ice.

[ShottsUZJ100]

Originally Posted by clownmidget

Have you tried the method used for the 80-series? Engage CDL with dash switch, drive @ approx 42 mph for approx 100 meters, then disengage CDL with dash switch, ABS remains deactivated...

What forum is this CM? You must be shopping for a 100?

[SamoL]

Today I did the "magic pin 7" conversion - and the central diff lock is now only manually operated. I've located the ABS computer, but there are just too many cables, to test them in all possible settings (with Hi/Low gear, CDL on/off, RDL on/off). If anyone posts a wiring diagram for ABS computer, I promise to post the full modification instructions with photos. There must be someone out there with a factory service manual - at least with a paper version - make a photo and publish it!

Regards

Samo

[100 TD]

By the way Samo, what year, model, engine, tranny, is your vehicle, do you have rigid or inependant front suspension, do you have a front diff lock?

[clownmidget]

Originally Posted by ShottsUZJ100

What forum is this CM? You must be shopping for a 100?

Just trying to help where I can Of course my first answer to this post was "Immediately trade your 100 for an 80 that actually lets you decide what the frick you want activated and when...

[SamoL]

It is a '98 HJD100 (with IFS) and with engine 1HD-FTE. But I guess ABS is the same on all J10.

Regards

Samo

[100 TD]

Nothing is necessarily the same on 100 series cruisers!!!!!!!!
I assume you have a manual transmission and I assume you have a rear toyota electric diff lock but not a front one. Can you confirm please. As previously mentioned, I don't have factory lockers, but I have 1HD-FTE and a 5 speed auto, and I don't have VSC or TRAC. I cannot disconnect CDL in low range and will probably go for the 7 pin mod, but "Bloodhound" has had trouble with his rear diff lock (indication?) and I am concerned if I utilise the difflock lamps in the combination meter (if I can find them) and possibly ECU as I wish to, that I may run into probs.

[SamoL]

Yes, I have a 5 speed manual and a Toyota electric rear locker (but no front locker). I did the "pin 7 magic". The only thing that bothers me now is ABS...
As far as I know, none of IFS 100-s had a front locking diff. And if you want to have a full time 4WD and a front locking diff, the only option is to buy an 80, or to upgrade the car yourself.

Regards

Samo

[100 TD]

Yes as far as I know you are correct with the rear locker only for the 100 IFS, but as I said, the 100 has many variants. My owners manual explains the use and availability of front and rear lockers, rear only locker, and no locker( as in not available as an option) and therefore the ECU's(or different ones) have to cater for these different options. My dash (combination meter) has lights on it for CDL (orange) which lights up, 4 wheel drive mode ( Green, doesn't light up), Rear diff locked (Red, doesn't light up) and front diff locked (Red, doesn't light up), so there are lots of different possibilities, and I hope to use the front and rear diff red lights and get them working when I switch my air lockers in. Only thing is, how will this fitt into the current ECU which is not ready for these inputs to be activated on this particular model?

[SamoL]

ABS has it's own ECU (located on he left above the clutch pedal - at least in my car). Main ECU (motor management) is behind the glove compartent (on the right). That's why I don't belive they've put in different ABS computers.
So do you have a wiring diagram or not?

Regards

Samo

[ShottsUZJ100]

Originally Posted by clownmidget

Just trying to help where I can Of course my first answer to this post was "Immediately trade your 100 for an 80 that actually lets you decide what the frick you want activated and when...

Excellent! Self control. I'm trying to learn the same.

[hoser]

Originally Posted by SamoL

If anyone posts a wiring diagram for ABS computer, I promise to post the full modification instructions with photos. There must be someone out there with a factory service manual - at least with a paper version - make a photo and publish it!

PM me your email address and I'll send you what I have.

[SamoL]

I did it! (thanx for the wiring diagram hoser)
I'll post pictures tomorrow, as it's getting late. But in short: all you have to do is to change wires on pins 6 (red & blue) and 7 (pink? & black) on a 16-pin connector on the ABS ECU (this connector is the middle one). This way engaging CDL will also turn off ABS. If you don't want ABS to be controlled by the CDL switch (if you want to controll it independently), you can switch off ABS by disconnecting wire from pin 6 (red & blue). To do so, use another switch.

Regards

Samo

P.S.: Modification suitable only for drivers who know how to brake without ABS .

[Jim_Chow]

This thread belongs should be archived!

[100 TD]

Well done Samo, you have just been voted by me as the gun to sort out all sorts of electrical problems and modifications!

[SamoL]

Well, I'm sure I'm not the one to sort ALL electrical problems, as I'm a computer programmer . But this one was easy.

Regards

Samo

[100 TD]

I did say "all sorts of electrical probs" and not a definitive ALL, but all sorts means I reckon you should have a go at just about anything! Can't wait for the breakdown of the fix with wiring diagrams, diagnostics, computer printouts, logic function block diagrams and updated TSB's back from Toyota!!
Thanking you in anticipation.......

[SamoL]

Here are the detailed instructions I promissed:
http://www.tojezakon.com/offroad/LC100_ABS/

Regards

Samo

[hoser]

Thanks for the write-up! Looks simple enough to post it here directly on the forum. It'll be here long after you change ISP's.

[dmc]

I'm sure you can figure this out on the 100. I did it on my old Tacoma. I rigged a manual switch on the dash that tricked the ABS into thinking the locker was engaged. It was a about 4 years ago so my memory is faded as to exactly what wires i tapped into but it worked flawlessly and I swear by having the ABS disabled. That way you can still disable the ABS without engaging the CDL if you didn't want to.
dmc

[SamoL]

Originally Posted by hoser

Thanks for the write-up! Looks simple enough to post it here directly on the forum. It'll be here long after you change ISP's.

You can do whatever you want with it . This is my own domain on my own web server on my own computer - so this site will be arround even after I change my ISP .

Regards

Samo

[SamoL]

IMPORTANT!

Something I forgot to mention: If you do the "pin 7 mod" (to enable usage of low gear without engaged CDL), ABS will no longer know, that low is selected, and will use normal ABS program when only low gear is selected. And when you additionally engage CDL, it will use ABS program as if only CDL was engaged (without low gear). So: I suggest not to do the "pin 7 mod" if you don't also do the mod described abowe.

Regards

Samo

[100 TD]

I'll ask the silly questions, Samo, do you have the LOGIC and CONDITIONS that the ABS works in its multi program mode? I would be very interested to get more info on this and other LOGIG for the LC100 as previously stated.

[SamoL]

There was a discussion ona LCOOL list (I'm sure you know about it). ABS on a 100 picks a program based on three parameters:
- Hi/Low gear
- CDL
- RDL (when RDL is engaged ABS is turned off)

If you disconnect the "pin #7", ABS ECU will loose one of the parameters.
That's all I know. I don't even have a service manual .

Regards

Samo

[100 TD]

I don't know about the LCOOL discussion, so what you are saying is, the only time the ABS is disabled is when the RDL is selected. Is this correct? and the ABS program changes depending on CDL and Hi/lLO selection. What changes does it make to the way the ABS works?
Thanks in advance
100 TD

[SamoL]

Originally Posted by 100 TD

I don't know about the LCOOL discussion, so what you are saying is, the only time the ABS is disabled is when the RDL is selected. Is this correct? and the ABS program changes depending on CDL and Hi/lLO selection. What changes does it make to the way the ABS works?

Correct. Only when RDL is engaged, the ABS is fully off (try it - you will see the ABS light on the dash). Program is changing so that it allows a little more wheel blocking when CDL is engaged and even some more, when in Low. But they gotta be kiddin'. The result is not so good. When driving with a CDL engaged and in Hi, you are not able to brake efficiently on gravell. And some people had also problems when driving in Low and driving down a steep muddy trail.

Regards

Samo