Now that you've re-charged the battery, check the voltage drop while
turning the key to crank the starter.
   BTW, those battery boosters will only assist starting a slightly low
healthy battery.  If it's really low or dead or not good anymore (old?),
those battery boosters won't help at all.
   I need to see the cranking voltage drop (or lack thereof!) to
troubleshoot further.

Mike B.

On 12/14/2012 7:14 PM, neil n wrote:
> Thanks Karl and Mike.
>
> DMM on battery, no accessories, ~ 12.6 Volts
> Headlights on, (are quite bright) turn key, headlights go out. DMM
> shows 11.8 Volts  (not a huge Voltage drop). I expected a larger
> Voltage drop when cranking starter.
>
> Last night, the small booster battery AAA guy used did nothing.
>
> Just connected battery charger. It displayed:  "67%"   12 Volts.
> Charged less than 1/2 hour, charger shut off and displayed "100%".
> Starter still doesn't work.
>
> Odd symptom (?): hand brake off, turn key to crank starter, the  "  !
> " light comes on.
>
> Maybe I should read the owners manual?     ;^)
>
> I did swap in a known good ECU but can't see how that would affect things.
>
>
> Neil.
>
>
> On Fri, Dec 14, 2012 at 1:43 PM, Mike B <mbucchino@charter.net> wrote:
>
>> Put a voltmeter on the batt posts and take a reading with nothing but
>> the dome light on, it should be over 12.5V.
>>
>> Then turn on the headlights only and see if the reading drops below 12V,
>> it should not drop too much, maybe 12.0.
>>
>> Then turn off the headlights, and crank the starter and see if the
>> reading drops well below 12V, it should not go below 11.5V.
>>
>> This should prove the battery condition, or the starter shorted if the
>> voltage drops sharply.
>>
>> Mike B.
>>
>>
>> On 12/14/2012 4:09 PM, Karl Wolz wrote:
>>> I've had dead batteries still put out 12+ volts; little or no amperage.
>
>