Dead car, no start - full battery?!

[TNTitan]

Strange thing happened today with my '09 3.8 non-tech. Drove to a restaurant with the wife and baby. Parked and shut off the car. As we walked into the restaurant, I hit the lock button on the keyfob and didn't hear a beep. I walked closer and tried again. No dice. I thought, maybe the Fob battery was low. (I have replaced the batteries about a year ago). Standing right next to the car, I got no response from the fob.

So I opened the door and tried to lock the car with the power lock switch. NOTHING. Now I'm starting to worry. I checked the other systems. Everything was dead. No dome lights, no dash, nothing. No electronics. Even putting the keyfob in the dash opening did nothing. No start whatsoever.

I read through the manual and searched around here for answers while the wife ordered lunch. I thought it couldn't be a dead, battery, could it? I mean, even a low battery would give me a little juice, right? Dash lights or dome lights or even let me lock/unlock. I thought there was a serious electric issue. Bad fuse, or loose battery terminals. Everything looked good after inspection under the hood.

I called for a jump start just to eliminate that option. When we finally got the jumper cables hooked up, I got power and the car SLOWLY started up. I drove the car home with no problems. I immediately tested the battery with my multimeter and the battery is reading 13V and my ammeter shows full charge. The car is showing no electrical problems now.

What gives? Anyone experienced this type of problem, or have any insight? Ive had this car for 2 years now with very few problems, but I don't want to be stuck dead in the water when I go out of town next week.

 

[homeofstone]

Check the ground wire from the battery in the trunk. The connection to the battery and where it bolts down to the inside of the trunk. Make both ends have a tight connection.

 

[Gunkk]

Get your alternator checked.

 

[TNTitan]

Check the ground wire from the battery in the trunk. The connection to the battery and where it bolts down to the inside of the trunk. Make both ends have a tight connection.

Connections are good and tight. Drove it today about 50 miles with no issues. Weird...

 

[TNTitan]

Connections are good and tight. Drove it today about 50 miles with no issues. Weird...

Belay that...

UPDATE: Car would not start last night at a friends house and no amount of jump-starting would help. Had to have it towed to the dealer (thank you Hyundai Assurance).

After a bit of diagnosis, they determined that in-fact, one of the ground bolts in the trunk was loose. Problem solved.

Hope this thread is helpful to someone in the future.

Thanks guys, especially homeofstone for the spot-on diagnosis.

 

[sandy]

Belay that...

UPDATE: Car would not start last night at a friends house and no amount of jump-starting would help. Had to have it towed to the dealer (thank you Hyundai Assurance).

After a bit of diagnosis, they determined that in-fact, one of the ground bolts in the trunk was loose. Problem solved.

Hope this thread is helpful to someone in the future.

Thanks guys, especially homeofstone for the spot-on diagnosis.

I know it's true with older cars, but guess it applies all around; start by checking the simple solutions

 

[Southern Boy]

Check the ground wire from the battery in the trunk. The connection to the battery and where it bolts down to the inside of the trunk. Make both ends have a tight connection.

homeofstone nailed it early on!

 

[TNTitan]

I know it's true with older cars, but guess it applies all around; start by checking the simple solutions

Yes sir. Occam's razor.

 

[sandy]

Yes sir. Occam's razor.

aka KISS