trouble with trouble lights 300e

[bclem]

my 1989 300e has developed an electrical gremlin that I need some help chasing down. It has some of the earmarks of a bad OVP but with a few twists. Here's what it's doing:

At rest (not running) batt voltage (BV) = 12.71

@ idle (600rpm) BV=12.30 and Batt lite & ABS light are on bright and all other trouble lights (including low fuel) are on

@1000rpm BV=12.49 all trouble lights are on but dim, Batt light is not as bright but still brighter than other lights & ABS lite is out

@1500rpm BV=12.70 all trouble lights out except Batt is on dim

@2000rpm BV=13.05 all trouble lights out & Batt is on very dim

@3000rpm BV=13.34 all trouble lights out and Batt is still on very dim

any ideas or suggestions would be very welcome.

thanks

[97civicdx]

Sounds like a dying alternator

[bclem]

Originally Posted by 97civicdx

Sounds like a dying alternator

a possibility but why would all the other trouble lights act so strangely ? i'd think if it was just an alt going bad that only the batt light would be involved ???

[bclem]

Well, I replaced the alternator and that fixed it. I still don't understand why ALL the lights were coming on though ????
Thanks for the tip :-)

[A264172]

When the recharge voltage drops the system cuts out non essential elements so the car can keep driving. What you describe is the usual for a dying alternator.

[saumil]

Also, if you look at the owner's manual, it mentions that a whole lot of lights will stay on when the charging system is not functioning.