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Discussion Starter · #1 ·
Vehicle: 90 4Runner
Engine: V-6 3VZE

The rear anti lock brake light comes on when braking on ice, Does this mean
that they are working or that I have a problem with them? No light on normal
regular braking under normal conditions. I haven't had this truck for more
than 6 mths, and I don't remember when I had my 91 4X4 if it even had anti
locks. Our Ford has 4 wheel anti locks and no light comes on when they are
working, but I do feel the pedal pulsating when they are working, which I do
not feel on the TOY.

Thank

Searcher
 
G

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Discussion Starter · #2 ·
Anytime the ABS light comes on it means the ABS system is not operating. ABS
should work transparently, you should never be required to do anything
beyond mashing the brake pedal. The system is designed to PREVENT the brakes
form locking, but ifthe ABS is not working properly, then the brakes can
lock when you are expecting them not to.

The ABS light warns you that the brakes will lock.

The pedal pulsates when the system is working. Since you do not feel the
pulses, the system is not working, which is what the light is telling you.




"Searcher" <[email protected]> wrote in message
news:[email protected]
> Vehicle: 90 4Runner
> Engine: V-6 3VZE
>
> The rear anti lock brake light comes on when braking on ice, Does this
> mean that they are working or that I have a problem with them? No light on
> normal regular braking under normal conditions. I haven't had this truck
> for more than 6 mths, and I don't remember when I had my 91 4X4 if it even
> had anti locks. Our Ford has 4 wheel anti locks and no light comes on when
> they are working, but I do feel the pedal pulsating when they are working,
> which I do not feel on the TOY.
>
> Thank
>
> Searcher
>
>
 
G

·
Discussion Starter · #3 ·
The 90s Toyota Trucks don't really have rear anti lock brakes like new
cars do. It's more of an anti-skid-to-stop-the-rear-from-passing-you
system. The Toyota uses oil pressue from the power steering pump to back
off the pressure on the rear brakes if the tires lock up. You won't fill
it in the pedal like you will with new cars with 4 wheel ABS.

If the light is comming on, then something is wrong. The anti-skid system
has a small computer under the dash behind the glove box. If you have the
service manual for the truck, you can jump two points on the diag block,
count the blinking lights, and it will tell you what is wrong.




On Thu, 15 Dec 2005 17:28:23 -0800, Searcher wrote:

> Vehicle: 90 4Runner
> Engine: V-6 3VZE
>
> The rear anti lock brake light comes on when braking on ice, Does this
> mean that they are working or that I have a problem with them? No light
> on normal regular braking under normal conditions. I haven't had this
> truck for more than 6 mths, and I don't remember when I had my 91 4X4 if
> it even had anti locks. Our Ford has 4 wheel anti locks and no light
> comes on when they are working, but I do feel the pedal pulsating when
> they are working, which I do not feel on the TOY.
>
> Thank
>
> Searcher
 
G

·
Discussion Starter · #4 ·
I will go out and get a book on Monday. The light ONLY illuminates when the
trucks wheels are on ice and snow and I am hittting the brakes HARD!

OK I was out playing in the snow, BUt the light has not come on even during
a few panic stops we had this summer.

Searcher
 
G

·
Discussion Starter · #5 ·
The light means the wheels, one or both on the rear axle (is my guess),
locks and the system can not prevent it from locking. This is the classic
definition of ABS not working.

Trucks typically have what is called 3-channel ABS, this means the two front
tires are controlled separately, and both rear tires are controlled
together. Your ABS valve body will have 5 tubes connected to it, two of them
go to the master cylinder, and the other 3 go respectively tothe left and
right front, and to the rear. Your truck _could_ have a 4-channel system,
and in that case there would be 6 tubes, and each of the rear tires would
get one of its own. You can also look at the rear axle to see if it is fed
by two brake lines or one. If there is only one, it will come somewhere near
the center, then split off to each side. You can find a brake line at the
wheel and follow it backward to see where it goes.





"Searcher" <[email protected]> wrote in message
news:[email protected]
>I will go out and get a book on Monday. The light ONLY illuminates when the
>trucks wheels are on ice and snow and I am hittting the brakes HARD!
>
> OK I was out playing in the snow, BUt the light has not come on even
> during a few panic stops we had this summer.
>
> Searcher
>
>
 
G

·
Discussion Starter · #6 ·
"Searcher" <[email protected]> wrote:

>Vehicle: 90 4Runner
>Engine: V-6 3VZE
>
>The rear anti lock brake light comes on when braking on ice, Does this mean
>that they are working or that I have a problem with them? No light on normal
>regular braking under normal conditions. I haven't had this truck for more
>than 6 mths, and I don't remember when I had my 91 4X4 if it even had anti
>locks. Our Ford has 4 wheel anti locks and no light comes on when they are
>working, but I do feel the pedal pulsating when they are working, which I do
>not feel on the TOY.
>
>Thank
>
>Searcher
>


remember that the anti lock / anti skid is disabled when using 4WD
(duh). Wasn't until 94 that that was added/remedied .
 
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