On-Board Diagnostics, or OBD, have saved Chevy Malibu owners and mechanics a lot of time in troubleshooting problems.
No more “okay, now try it” trial and error, you just plug your device in. Of course, P305F is just a bunch of numbers if you don’t know what it means.
So, what does P305F mean on a Chevy Malibu?
Simply put: Something’s wrong with your dual battery control module. More specifically, you probably need to take a look at the little battery in the trunk of your car.
Now you’re probably wondering: How do I get that taken care of, and why is there a second battery in the trunk in the first place? We’ll answer these questions below, and give you a step by step guide to handling code p305f. Read on.
Why Does the Chevy Malibu Have Two Batteries?
The Chevy Malibu comes with an auto-shutoff feature. If you’re idling for a long time or certain other criteria are met, your engine will turn itself off to save on fuel, fluids and wear and tear. This helps you get a lot more miles out of your Malibu.
When your car starts up again, it’s going to use the main battery to do that. The second battery is there to keep your interior lights, radio and other electronics running while your primary battery sends all the power into the engine to get it started.
It’s a basic quality-of-life issue, a neat little feature to make sure you don’t miss your favorite part of a song while your car restarts. As for why it’s in the trunk, that’s just a handy, out-of-the-way place for a small battery.
I’m Getting Code P305F, What Do I Do?
The problem could be coming from the wiring around your primary battery, or it could be coming from your trunk battery. Before you go buying a new trunk battery, take a look under the hood for anything loose or misplaced. Here’s what you’re looking for:
- A loose ground located right in front of your primary battery
- Make sure the wiring harness near your battery isn’t rubbing up against the body of your vehicle
- Under the fuse block, you might find that the fuse nuts are loose
- If you’re having trouble finding any of these parts, this video will let you know exactly where to look, and what they look like
If all of that seems to be in working order, open the trunk and pop the battery panel. If it hasn’t somehow come detached, then the next step is going to be testing the battery.
Use a ten-millimeter nut drive to loosen the nuts. Start with the mounting bolts, then the cables.
Remove the cables, negative first, remove the battery, and remove the vent tube from the back right corner of the battery.
If you have a battery tester, you can go ahead and test the battery. If you can’t test the battery, rest assured that almost every time you have p305f, if it’s not a problem under the hood, it’s a bad auxiliary battery, so buying a new one is probably the right solution.
Handy Features
The backup battery is a really neat feature of the Chevy Malibu. Obviously, we buy cars based on performance and reliability, but features like these can be the tie-breaker. If you want to know what your new car comes with, check the Vehicle History.
