How do I know if my alternator is going bad

 

When mine failed, the Charging System Indicator (battery) light came on. Everything seemed fine at first but the battery drained and shortly thereafter the instrument cluster lit up like a Christmas tree, the speedo and tach stopped working, etc. I was able to jumpstart the car to get it to the shop, but the instrument cluster continued to fail. Replaced the alternator and everything was back to normal.

 

If the charging light is on, you are driving on borrowed time (less than 15 minutes before shut down). You can get a load test for free at most auto parts stores that can test alternator capability.

 

I had my alternator fail on my RDX and TSX recently (both with +130K). The RDX alternator wasn't putting out enough volts to recharge the battery and power the vehicle. The battery would supply the needed power until the voltage fell too low. I would then get the X-mas lights all over the dash and the RDX would die. The TSX alternator was working the day before and died the next. It is the kid's car and he didn't "see" any warnings or lights (I figure he just didn't notice the warning lights). Since the alternator didn't charge the battery, it drained it to almost zero before dying on the side of the road.

Having a $50-$75 battery charger/maintainer at home is good way to top off the battery and be able to drive it to the repair shop instead of call a tow truck.