92 Bonneville antilock system problem

[Alpha One]

The other day I went over a big puddle and there was a big bang, of course.
Immediately after it, the antilock-brake light turned on. It never turn off
again except for a few minutes the next day. I removed the tire and checked
wiring and suspension and every thing seems to be fine. The car brakes as
before except the anti-lock part won't work. Any idea what could it be?

Tony

[GTP Dad]

This sounds like the antilock sensor has gotten wet and is probably going to need to be replaced. The other item would be to make sure the connector is connected and clean internally. Otherwise replace the sensor and the problem should go away.

[richtazz]

you can check sensor resistance, as tested across the abs harness, it should be about 1K ohms. If not, the sensor is bad. Common problem on all GM vehicles that have the ABS sensor contained in the hub bearing.

[Alpha One]

The resistance was 1000.6 Ω. I checked the connectors and they look good. But I never had a problem at all. The light turn on as the right front wheel hit the pothole. (I wrote puddle on my previous posting, sorry about that).
It just occurred to me; maybe I should also check the rear wheel. I am sure it went over the pothole too.

Originally Posted by richtazz

you can check sensor resistance, as tested across the abs harness, it should be about 1K ohms. If not, the sensor is bad. Common problem on all GM vehicles that have the ABS sensor contained in the hub bearing.

[maxwedge]

Originally Posted by Alpha One

The resistance was 1000.6 Ω. I checked the connectors and they look good. But I never had a problem at all. The light turn on as the right front wheel hit the pothole. (I wrote puddle on my previous posting, sorry about that).
It just occurred to me; maybe I should also check the rear wheel. I am sure it went over the pothole too.

To add to Richtazz's answer you should have it scanned for wheel speed sensor readings on an abs function scanner, I have seen them pass the resistance test and not generate a wheel speed.