Hey all,
My friend has a 97 GMC Jimmy and I was driving it today. I parked it for maybe 10-15 minutes and when I came back, it wouldn't start. It was acting like it didn't have enough battery voltage, where the interior/dash lights were really dim and the buzzer sounded lethargic. When the key was in the ON position, the lights and buzzer were normal, but when I turned it to START that's when the low voltage-like behavior started. Wouldn't crank at all and I didn't hear any clicks or anything. Battery voltage was just under 13. Jump starting didn't help. I noticed that when I pressed on the brake, the buzzer and interior lights turned off completely as if there wasn't enough voltage available for brake lights and the interior lights/buzzer. When I let go of the brake, buzzer and interior lights came back (lethargically.) I'm super unfamiliar with these cars and GM cars in general as I drive a Toyota Land Cruiser. With the Land Cruiser, I'd suspect an issue with the fusible link, one of the main fuses, or a ground issue, but I'm not sure where to start with the Jimmy. Any ideas? Thanks in advance.

 

1. Take off the battery terminals, wire brush and clean everything and then retighten both battery cables
2. Get a meter on the battery terminals and tell me the battery voltage at 1) rest, 2) key on, 3) ignition in the start position

Report back and we will go from there.

George

 

How old is the battery.

It is not enough that the battery have a large enough voltage, it also must be able to supply a large enough current.

Cleaning the battery connections as George suggested can help with the lack of current.

 

I pulled off the battery terminals, sanded everything down, reattached, and now it works perfectly. Thanks guys. Now to figure out why the front parking lights are crossed with the front turn signals...

 

Glad your running again


George