My Hybrid Truck Battery Swap Story

[D0minicTorre]

I got my hybrid truck a year ago, and it's got 9,000 miles with almost no problems. But for the last 8-9 months, I've had this annoying 12-volt battery issue where it goes into deep sleep, and the inside lights stop working. It's never left me stuck, though. The final push was when my wife and daughter got in at night and wondered why the truck had no lights. I had to laugh.

When the problem hits, the voltage under the hood shows around 11.4 volts. I've charged the battery a bunch with a good charger, and it powers up fast, but the issue keeps coming back. I didn't want to deal with the dealership, waiting a week, risking scratches, and getting excuses. So, I spent $230 on a new Diehard Gold battery, made last month, matching the old one perfectly. I swapped it myself to make sure it was done right and to rule out a bad battery.

Switching it out was a hassle holding cables, bending over, wrestling with the bolt. You just need a 10mm socket and a long extension. Heads up, that bolt will drop, and you'll need to fish it out. After the swap, the lights worked again. I did the reset trick with the high beams and brake pedal, locked it up, and left it overnight like the manual says.

I checked the 12-volt cable before and it felt solid, but I didn't dig into the wiring. At least now I know it's not the battery.

 

[Try_Sky]

Bummer about that persistent 12 volt issue in your hybrid! sounds super annoying with the lights. Good that you did the battery swap yourself to rule that out. hope the new battery solves the problem!

 

[Hercules]

Good call on swapping it yourself, let's hope that was the magic fix

 

[Zelph]

If it is running down gradually with use you are possibly not getting normal charging when driving.
Or, some current drain while sitting.

Check the Alternator output. If OK, keep close watch on 'ghost' draining. Stuff like the wiper motor or similar still taking current with the truck sitting and off. Ran into this with a Ford Escape - the rear window motor would drain the battery over a few days of sitting. Pulled the fuse after charging & it stopped losing the charge. Then replaced the motor & all is well.

Good luck, electric drain can be hard to track down.\

If it is under Warranty, bite the bullet & get it checked out. Coming out of something at night to a vehicle that won't start will be much more inconvenient than some time at the dealer.

 

[Reagan L.]

Nice job taking it on yourself. Agree with @Hercules here. Hopefully that new battery holds up, but yeah, worth checking for any parasitic drain just in case.