ABS self-test

[fordnmerc]

I have been reading elsewhere that on various ABS-equipped cars, every time you start out the system does a self-test. On my 1996 Grand Marquis it seems to do that in about the first 50 to 75 feet of forward movement. The ABS system will make a sound like a squeak for a moment. (I thought at first that it was the serpentine belt making the noise.)

However, every time the ABS system does that, the headlights dim for just a moment also, regardless if any other accessories are being used or not.

Is that normal?

Thanks....I really have not dealt with ABS much before this.

[jaywish]

I have never had the abs do that.

I you are sure it is the ABS, because the ABS light comes on during the event you describe, then the easiest thing is try to clean the front pickups & tone rings.

It could be a caliper hanging up, but I have never seen that reaction. Perhaps someone who has experienced the same thing will post up.

[gadget73]

Sounds like a current draw issue. The headlamps and the ABS should not be related in any way, other than they both draw off the electrical system. If it fires the pump as part of it's test, that might explain it. I honestly do not know if it does that though.

The self-test is during the first couple of seconds after the key is turned on. If your ABS pump kicks on at low speed, that sounds more like smeg in the tone rings.

[DerekTheGreat]

...If your ABS pump kicks on at low speed, that sounds more like smeg in the tone rings.

smeg·ma

noun: smegma

a sebaceous secretion in the folds of the skin, especially under a man's foreskin.

[fordnmerc]

The ABS light has never come on with this.

Right now there seems to be a short somewhere at the back end of the battery cables. Everything was electrically dead and then when I wiggled the wires around and kind of shoved them back in the corner between the valve cover and the air box for now the electrical connection is back. It's just very cramped from both the topside and underneath and I have not had the opportunity to really inspect the cables on that back end.

When I have the opportunity to replace the full length of the cables then I will see if the ABS and headlight issue remains and go from there.

Something was draining batteries for quite some time. I suspected the radio because the on/off push button would not work and the radio was on all the time. I completely unplugged that. No change. I removed every single courtesy light throughout the whole car. No change. Fuses are all fine.

I began unhooking the battery after every trip so that the battery would not be drained down to nothing overnight.

Then the other day everything was dead electrically even with hooking the good battery up as usual. That's when I found the apparent short in the cables at the back end after moving them around a bit and having the power suddenly return.

So, new cables will be the first order of business and next will be trying to find out if there is possibly a second short or power drain from another source.

My wife and I half-jokingly tell each other that there is something hanging around us, because of unexplained electrical anomalies in our house that come and go and the fact that we had 2 other cars in 10 years that we had to get rid of because of electrical problems that could not be tracked down. In the house one time, there was a smell of ozone so very profoundly strong and localized to one spot that I was convinced that there was faulty wiring in the wall and that a fire was imminent. Upon thorough investigation of every possible source, absolutely nothing was found. The smell gradually faded away and did not return.

It makes a person feel like they're haunted.

[gadget73]

smeg·ma

noun: smegma

a sebaceous secretion in the folds of the skin, especially under a man's foreskin.

you smeg head.


clearly not a Red Dwarf fan.