Car cranks but doesn't start

[blue62]

Originally Posted by mikehkang

Hello Experts,

I have 2001 base 986.
For about a week, I have had intermittent starting problem. I can hear the car crank but it won't start.

Questions:

If you have your headlight turned on BEFORE starting the car, is it normal that the headlights go dark? (I think the lights going dark is the proof that I have a bad battery but both Pepboys and Autozone tell me that my battery, about 3~4 years old, is good as it holds 80% SOC.)

I have wonderful headlights I bought from Nine8Six.
Can anyone with setup like mine check if the headlights go out as you start?


What's done so far.
- I am ruling out the alternator as I can measure 14.30ish volts from the battery terminals.
- As long as the battery is hooked up to my NOCO G3500 charger, the car starts without problem. (I may have first 2001/986 EV Boxster, ever. )


Thank you in advance.

what is 80% SOC????
Percent of charge or voltage reading is meaningless.
You need Amps.
What you want is a load test done on the battery.
That tests cold cranking Amps
With that said if the car will only start with charger hooked to the battery then you need a new battery.
Also the light going dark is when you try to start the car is another sign that your battery is toast.