Volvo S40 2000: Battery, Brake, and ABS lights

I have a 2000 Volvo S40 that I bought used in 2004. I live in a very mountainous area, and often have to drive up very steep hills to get home. Whenever I get to the steepest part of the drive, the Battery, Brake, and ABS lights all come on on the dashboard. This is accompanied by something like a seizure of the car, as if it goes into Cruise on its own. The lights on the dashboard flicker, and the high beams sometimes come on.



I took it into the dealership, and they installed new battery cables, but that didn’t do the trick, the lights still come on. It has progressed to the point that the lights come on on flat ground, sometimes when rolling into a stoplight. They’ve checked the brakes and ABS, and they’re in fine condition.



Any ideas of what could be wrong?

I would have the charging system checked. Many auto part stores will do that for free.

I don’t know what kind of system monitoring a 2000 Volvo would have, but I would guess it does record error codes for certain problems. Have you checked to see if there are any error codes stored.

BTW don’t bother with the dealer. They have already proven they don’t know what they are doing.

I agree with JEM about the alternator as a possible cause of the trouble and would be my first suspect or posssibly in the wiring to it. The warning lights are tied to the alternator circuit so that could explain why those are turning on. The high beams turning on though kind of leaves me with a question of how that could be happening.

My guess is that the engine is dying at the steepest part of the hill. By all means have the charging system checked, but have the engine checked out too.