Problems with battery draining for no ‘obvious’ reasons.

ANSWER : Hi there. It’s quite possible that you have one of two things causing the drain to the battery. First, you have a bad ground somewhere in the main relay or fuse box or an exposed wire somewhere that is not allowing the circuit to complete from the alternator to the battery. This can cause a battery draining issue as you’re describing, but it could also be one of multiple other electrical problems. The best way to pinpoint the exact source is to have a professional mobile mechanic come to your location and complete a battery will not hold a charge inspection.

ANSWER : This problem can be diagnosed by connecting an ammeter to the positive (red) battery cable, observe the current drain (likely less than 1 amp). Then, one at a time, remove each fuse, check to see if the current drain has dropped to near 0, then reinsert the fuse. This process should identify the faulty circuit in most cases. A professional mechanic, like YourMechanic, can perform this procedure for you, and replace/repair the failing component.

ANSWER : Hello there, thanks for writing in about your 2009 Chevrolet Aveo5. Batteries that drain overnight are not uncommon. This is called a parasitic drain and can have many different causes. The most likely are any aftermarket electrical accessories, such as the radio, a power seat, window switch, dome light or wiring fault. I recommend having a certified technician look over the vehicle’s electrical system in order to diagnose why the battery keeps draining and make the necessary repairs.

ANSWER : Hello – this problem can be diagnosed by connecting an ammeter to the positive (red) battery cable, observe the current drain (likely less than 1 amp), then, one at a time, remove each fuse, check to see if the current drain has dropped to near 0, then reinsert the fuse. This process should identify the faulty circuit in most cases. The specific components on that circuit can then be checked for current drain problems. A professional mechanic, like YourMechanic, can come to your location, and perform this procedure for you, and identify, replace or repair the failing component.

ANSWER : Auxiliary batteries can take awhile before symptoms may be noticed on a Prius. This is due to the hybrid system powering many of the components. In this vehicle the auxiliary battery is mainly used for starting. It could cause problems if not installed properly.

I’d recommend getting some help from qualified technician who will be able to diagnose the source of your battery issue and assist you with any repairs that may be necessary.

ANSWER : Hi there – yes, something is going on here that’s draining your battery. Perhaps the pressure of the engine wash dislodged wiring which has shorted, or there was a chemical reaction to the cleaning solution that caused electrical damage in the alternator or voltage regulator. These componnents can be checked off of the vehicle. Vehicle wiring can be diagnosed by connecting an ammeter to the positive (red) battery cable, observe the current drain (likely less than 1 amp), then, one at a time, remove each fuse, check to see if the current drain has dropped to near 0, then reinsert the fuse. This process should identify the faulty circuit in most cases. The specific components on that circuit can then be checked for current drain problems. A professional mechanic, like YourMechanic, can come to your location, and perform this procedure for you, and replace/repair the failing component.

ANSWER : Hi, thanks for writing in. This may be a sign of a failing starter relay. The starter relay is a small unit near the starter that directs power to the starter from the battery. When this fails, it may cause a clicking sound and will not allow the starter to engage the flywheel when you turn the key. I would suggest having a professional from YourMechanic come to your home to diagnose your starting issue to determine the solution to get you back on the road.

ANSWER : Hello there, thank you for asking about your 1957 Chevrolet Bel Air. Checking for parasitic draw on a battery can be done by inserting an ammeter in series with the negative battery cable, then removing the fuses one by one until the draw drops. Once this happens, you have found your problem circuit. A professional, such as one from YourMechanic, can [find the problematic fuse and replace it for you](https://www.yourmechanic.com/services/fuse-replacement]. In regard to your instrument panel, unfortunately, I do not have the wiring diagram for your vehicle due to the age. The instrument panel will need to be checked for both power and ground to determine where the problem is. Once again, a technician from YourMechanic can inspect your electric problems.