OT: ABS light on problem / question - 95 Pathfinder

[J Miller]

95 Nissan Pathfinder with rear only anti lock breads.

Just recently the "ABS" light has come on and stayed on. I know this has something to do with the anti-lock break system but don't know what exactly to look for.
The breaks are working normally, nothing feels different at all.

I've done a cursory look at the hydraulics and haven't found any signs of leakage, and this after noon when it cools down a bit I'm gonna check it underneath for loose wiring connections and anything else I can see.

What else should I look for?

Joe

[williamranks]

Could be one of the wheel speed sensors has failed.

[J Miller]

Could be one of the wheel speed sensors has failed.

OK, I know where that is. This one has a single sensor in the differential.
I'll just have to figure out how to test it.

Joe

[TedH]

Without an oscilloscope, all you can do it ohm test the speed sensor. Should have roughly 2 or 3 ohms resistance across the two terminals, but some makes are 10-12 ohms. If it's bad, it will most likely just be an open circuit through the sensor.

[J Miller]

Without an oscilloscope, all you can do it ohm test the speed sensor. Should have roughly 2 or 3 ohms resistance across the two terminals, but some makes are 10-12 ohms. If it's bad, it will most likely just be an open circuit through the sensor.

I got an ohm meter. Should that be tested with the harness unplugged or all plugged in and operational?

Joe

[madman4570]

Some people would say just put a piece of black tape over light on dash!

Try washing the wheels really good at a car wash.
Concentrate on getting at as much of the inner wheel as possible.
My maxima in the summer does same thing(dirty sensor)wash it and it goes away.
If that don't work,disconnect the negative battery terminal over night,reconnect and see if that does it.
Have you tried when safe to do so,hitting the brakes fairly good(pedal held in to feel anti kicking in)

Otherwise,if it(the brakes are stopping you good,just run it)should'n't hurt a thing.

I am no great mechanic so any of my recommendations are just that(OJMO) so do whatever at own risk.
Good Luck

[TedH]

Without an oscilloscope, all you can do it ohm test the speed sensor. Should have roughly 2 or 3 ohms resistance across the two terminals, but some makes are 10-12 ohms. If it's bad, it will most likely just be an open circuit through the sensor.

I got an ohm meter. Should that be tested with the harness unplugged or all plugged in and operational?

Joe

Unplug it and test across the two terminal of the sensor.

[J Miller]

Without an oscilloscope, all you can do it ohm test the speed sensor. Should have roughly 2 or 3 ohms resistance across the two terminals, but some makes are 10-12 ohms. If it's bad, it will most likely just be an open circuit through the sensor.

I got an ohm meter. Should that be tested with the harness unplugged or all plugged in and operational?

Joe

Unplug it and test across the two terminal of the sensor.

OKee DoKee, I will do that.

Thanks for the assistance.

Joe

[adirondakjack]

Ya might find the connector at the sensor is fragged.

[RKrodle]

My neighbor owns a garage in town and when I asked him about my light coming on he said to tape a picture of my granddaughter over it and keep going. I did.

[J Miller]

Ted,
Checked the sensor, nothing, nada, ziltch, not even a twitch on the ohm meter.

Finally found the section in my Haynes book covering diagnosis and it says to ground terminal 3 in a little "Check" connector under the dash. Supposedly the warning light will flash a number of times to indicate what's wrong.
The only thing is, it shows the connector for 91-93 being set up one way, and 92 as another, but doesn't show 95. I'm not getting warm and fuzzy feelings about grounding out something when I'm not really sure it's the right something.

I suspect the sensor is toast by the "OL" reading on the ohm meter though.

It's going to be a royal witch to replace. It's bolted directly to the front of the differential. The drive shaft flange has to come off first.
OH WHAT A PAIN!

A-jack,
That's the first thing I looked over. All the wiring connectors are in great shape.

Joe

[J Miller]

Ricky,

I just might have to do that. But I think I'll put a pic of Kylie Minogue there.

Joe

[Hagler]

Joe,

How is your brake fluid level? Many vehicles have a "brake fluid level" sensor, or float, in their master cylinder's reservoir. If your fluid is low, or that float is sticky/ bad/ unplugged, then your anti-lock brakes won't work.

Shawn

[TedH]

Low brake fluid will not make the ABS light illuminate, the red brake light yes, but not the ABS. The "OL" on your ohmmeter is a sure sign the sensor has failed.

[J Miller]

Shawn,
It's down a wee bit but nowhere near the "MIN" line.

Ted,
Thanks.

I guess I should print up that pic of Kylie. It's gonna be a while before I can do anything about it. Maybe this one:

kyliegreenfairylarge.jpg

I always did like fairys.

Joe

[williamranks]

The one on the diff should be the vehicle speed sensor. The wheel speed sensors are at the back of the wheels.
Look for wires coming from the wheel hub. They're not cheap!

[J Miller]

The one on the diff should be the vehicle speed sensor. The wheel speed sensors are at the back of the wheels.
Look for wires coming from the wheel hub. They're not cheap!

No wires on the wheel hubs. This one has only the sensor on the differential.

As for not being cheep, nothing for an import name plate is.

Joe

[BAGTIC]

Had the same thing happen to my Buick Century about 10 days ago. Took it to a very reliable shop in town. The ABS controller had failed They informed me that since the light came on we had been driving with only front brakes. As this is my wife's work car, 6-10 miles a day - in town only, she might never have noticed she did not have rear brakes until an emergency demanded them and then it would have been too late.

[J Miller]

Had the same thing happen to my Buick Century about 10 days ago. Took it to a very reliable shop in town. The ABS controller had failed They informed me that since the light came on we had been driving with only front brakes. As this is my wife's work car, 6-10 miles a day - in town only, she might never have noticed she did not have rear brakes until an emergency demanded them and then it would have been too late.

OUCH!!!!! I had a big Buick that ended up with rear breaks only when the replacement power booster was somehow defective. I know how that feels.
Luckily the break on the Pathfinder are working good. Only the Anti-Lock is out. To be honest I don't give a care. Never was a fan of anti-lock breaks anyway.

Joe