Do all Bonnevilles have that?

what is the purpose of turning it off vs leaving ti on?

thanks

With it on you cant leave much of a patch, just a little spin then it activates.

I think the SSEi is the only one that has it, maybe the SSE.

My 1993 SLE has it.
I dont think that all SE'* got it some do though
SSE and SSEI'* have it though

Thats why I thought it would be the SSE/SSEi cuz my car doesnt have it.

The purpose of it is to sense what speed your wheels are turning (in comparison to each other) while accelerating, or if they would go into lockup when brakeing. They are solenoids that pulsate your brakes to maintain tire speed rotation with each other. They will hold the wheels back to prevent traction loss while accelerating to hard, or releases them by pulsating if they go into lockup :? make sense? Thats why you feel a pulsating if you brake real hard, but not to be mistaken by a wobbling set of wheels

Main purpose is for bad weather like rain, snow, ice, etc so you decrease the chance of saying "hi" to a gaurd rail.

Ummm, isnt that what the ABS is.

Yup, she asked what the purpose was!

She was asking for traction control, not ABS. Traction control is only taking off. All that does is reduce the power so you can catch grip.