I have a 2000 f-150 lariat 4x4 ABS 5.4L. every time I turn the key foward just so the lights and stuff comes on not where it starts the truck, I can hear a soft grind or clicking I have pin pointed it to what I think is the abs computer it has 4 brake lines coming out of the back of it and a wiring harness out the front. This will do this no matter what I do when I turn the key forward to run position or as soon as I start it and the key goes to the run position it will do the soft grind it only last maybe 2-3 seconds then quits. Is this a bad computer please help me
Thanks

 

That sound is the ABS system performing its power on self test (POST). It is actuating its valves and the pump as part of the test.

Completely normal.

Now, if the ABS light stays on, you've got a real problem.

Steve

 

Ditto. Mine does it too (although mine is a more abrupt thunk as the valves cycle). The dealer was stumped the first time too.... finally narrowed it down.... completely normal part of the self-test. Some of them are quiet, some of them are not. You and I got loud ones. Nothing to worry about though.

-Joe

 

No Abs light so this helps me put myself at ease thanks for your help everyone