Is my ABS module bad?

[NeoTokyo]

Heya everyone, quick question about my brakes.

I am not sure if the module is bad or if there is something else going on here.
I thought maybe the rotors were warped but after some repeated hard stopping today, I don't think that is the case.

The brakes are stock 30mm aluminum's with EBC Greenstuff pads on all 4 corners.

Symptoms

* Mileage Trip counter does not work (I read that could be a symptom)
* Brakes can vibrate like I have badly warped rotors at semi-light to medium brake pressure coming down from freeway speeds.
* No vibration when brakes are pressed harder, spirited driving.
* Very limited brake pedal travel, very stiff. I would say 2" of travel.
* Brakes (Front) lock up on very hard braking but stop shorter than my old 93' 2+2.



Thanks everyone.

[DCaff300ZX]

Two things to consider:
1. Nissan front brakes have a runout issue that Nissan knows about but let go anyway, and which causes the symptoms you describe. The result is that you either turn the brake rotors on the car as the TSW suggests, or change out brake pads at around 50% to keep a steady pad pressure on the rotors and minimize the runout issue. Your choice.
2. Brakes locking up suggests an issue with the ABS system, or sticky caliper pistons needing rebuild (very common). There is a sticky at the top of the Z32 page with "everything you need to know about the Z32" and a downloadable FSM with tests for all of the various systems in the Z32 that will supply tests for the ABS module and system, while brake rebuilding and or replacement stands on it's own as to what to do.
Good Luck!