When my truck isn’t started for a couple of weeks, battery will be dead. Going on for years. Any ideas?

 

might help to know the year of the truck and any aftermarket additions, bone stock etc.

A "couple of weeks" might not be unusual with all the electronics. There are a few threads on how measure the draw on the battery with the vehicle off with a volt meter and then how to chase it down if the draw is abnormal. If it's taking weeks to drain it I'd just throw a battery tender on it and call it good.

 

From his previous post it suggests he has a 2010 model with the 5.4 3 valve engine. Every time your battery goes dead, expecially if it has happened in cold weather, the battery never fully recovers. I would get a new battery, perhaps one the next cranking size larger, and use something like a NOCO 10 charger plugged into wall AC outlet to keep the battery up to spec.

Check your glove box light that the switch works and the light goes out when closed.

After that an amp meter would need to be installed to see how much battery draw there is when the truck is parked. With pulling of separate fuses to isolatd which circuit is not going to sleep like it is supposed to.

 

Ignition, console shifter are the most draw common problems in our gen. But, it's 15 years old. Lots of potential due to age.

 

Not sure when they started doing this but on my 2024 RCSB 5.0 if I don't use it for a couple of days it goes into a sleep mode (seems dead) until I put the key in. Not even a light inside or cargo lite until the key is inserted.

 

Get new battery, plug NOCO battery maintainer into 110v AC outlet, clip red lead on battery positive black lead onto engine block bolt. Disconnect this 2 wks later when you drive it again.

 

Picked up an H7 today at Costco $180. H8 was same price but wanted to avoid any potential figment issues caused by the larger battery with just 50 more CCA.

It's on a charger overnight and will be installed tomorrow.

The old battery was just struggling to keep enough power in it with these 10deg F temps.

 

about 20 years or so ago

 

Check your Dash Cam is powering down if you have one.

 

Let's say a healthy battery has 65 AH capacity. Two weeks is 14 days. A load of 0.19A/hr will fully drain it in 2w. A cell phone charger left plugged in could do that.

Now let's say the battery is unhealthy and only has 45AH capacity. That's 0.13A/hr in discharge. That's a very reasonable rate of discharge sitting parked.... well, maybe a little high but not by much.

Replace the battery, and put a battery tender on it since you don't drive it that much.