I was driving and somebody pulled out in front of me and after I slowed down pretty quickly my battery light came on. I had it tested and it was fine, alternator is fine also, and all the grounds coming off the battery are tight. Any suggestions?
Battery might be low. If you have ABS in your car, when the car needed a lot of power to kick on the ABS, it may have drained the battery a tad to cause the light. Just a guess though?
The battery light stayed on though. Still on. My voltage is around 11 volts right now and my ABS light also came on tonight. It fluctuates between 12 and 14 since an under-drive pulley was put in. Only now it's just sitting at low 11s and 10.8 with headlights on. I can tell the voltage with the radar detector and it is slowly decreasing each day by a tenth or two volts. It seems as if the alternator is slowly giving up rather than just dying. Does that sound right. The battery is brand new also.
Sounds as though the underdrive pulley mod has reduced the rotating speed of the alternator to a point where it can no longer produce sufficient output to match the normal running loads. I would guess that with the standard pulley setup this problem may go away. The alternator voltage is designed to be at 14-14.5 volts, anything less and the battery will be discharged over a period of time
Alont
Do they make a alt that will keep up with the underdrive pulley. Somebody mentioned a 180 alt rather than the 105 the car comes with. Only thing about this is that this came suddenly after a quick stop I mentioned. The radar was showing it going from 12 to 14 then all of a suddedn its staying at 11 now.
As I understand it ---The purpose of the underdrive pulley is to "Gear down" the drives to the accessories so all works well if you drive fast everywhere!
I think your alternator was slowly losing the fight to keep your battery charged, as it was rotating slower than before and Exodus was correct, the extra drain from the ABS demand tipped the voltage below 12.
I would recharge your battery with a battery charger as soon as possible, because they don't like to be below 12volts for long before they exit!
Even putting on a high output alternator would not cure the problem unless it was rotated at a high enough speed to generate sufficient electricity to keep your battery charged, the alternator you have fitted now will do that if it rotates fast enough/often enough.
Remember alternators do not normally produce their maximum output until the engine is running at the same RPM as it would do at normal cruising speed.
All I could think of to solve your problem is to:-
1. Fit a smaller diameter alternator pulley, they are available, at alternator specialists
or
2. Revert back to the standard crankshaft pulley
Good Luck
Alont
