Complete loss of power with key turn


#1

My daughter drives a 94 Century (120+ K) and it was running great, no issues to speak of. Thursday morning she was advised that her brake lights were stuck on when the car was parked in school lot. This drained the battery. The battery was very old so she got a new one properly size & installed; the car started up and drove fine. Later that evening it started up and drove again with no issues.
Next morning; NOTHING; No Start. I checked and when door is opened interior lights come on, insert key and door chime rings. Turn key and there is nothing at all, a total loss of power, lights go out, door stops chiming but nothing. Starter never engages, no noise, no attempts of the engine to turn, remove key and lights return and door chimes!
PLEASE HELP!

1994 Buick Century 3.1L SFI OHV 6cyl ~ $hade-tree mechanic (due to cost control)


#2

The lights are controlled by a switch at the brake pedal. It might be as simple as it’s sticking…or it’s shorting out…or some other wire is shorting out…

A starter requires a LOT more power then lights…you may have lights and stereo…but the amount of current they draw from the battery is less then 1% of what a starter will draw when trying to start the car.

You need to trace it with a volt meter.

What you can do in the mean time is when you park the car remove the fuse for the brake lights.


#3

After you make sure the brake lights are not still on, remove and clean the battery cable connectors…If the connectors are badly corroded, replace them with new ones…


#4

Sounds like there is still a current drain on the battery.

The symptoms you are describing (dome lights, chime, but no crank or solenoid click) are what happens when you attempt to start a car with a nearly discharged battery. (Especially that the dome lights and chime go out when you try to start.)

You need to:
(1) Determine the battery voltage at rest. It should be 12.5 V or so; anything less than 10 would explain the no-start all by itself.
(2) Determine the source of the current drain and fix. This can be done by measuring load with the key off, pulling one fuse at a time, and figuring out which one is responsible for the current draw.