Battery gets drained, recharging the battery

ANSWER : Hello, the best thing to do in your case is to install a battery shut off switch. However, you are indicating that your battery is perhaps not accessible enough for such a retrofit. And, of course, if you disconnect the battery you lose anti-theft (alarm) protection as well as the possibility of losing stored info in the PCM.

Generally, the issue with charging in situ is if the charger has a voltage excursion (above 14 volts) which, if it occurred, could damage the PCM and vehicle electronics. Just to be on the safe side, Jaguar simply just says to disconnect the battery. If you are using a high quality professional charger, you are probably safe in leaving the battery connected while charging.

The charging circuit is running through the battery and the likelihood of runaway voltage if you are using a decent charger is low. Note that, even if you use a shut off, lead acid batteries will self discharge anyway, so you will still have to charge the battery every several weeks if you are not using the car. Watch out for gas in the tank oxidizing. Keep the tank full and use fuel stabilizer applied to fresh gas. If the gas goes bad and plugs injectors, you will wish you had "only" a dead battery. If you are continuing to have problems with your battery, a qualified professional from YourMechanic can diagnose the charging issue so that you will not have to keep charging it.

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 : 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. It is possible that the your 2003 Lexus SC430’s computer is draining the battery during the time that it is not being driven. It is never a good idea to let a car sit for extended periods of time without the engine being run or driven.

If this problem only happens after the car has been sitting for a week or so, this may be caused by something else. Running the engine or driving the car may solve the problem. If it does not, it is also possible that there is a problem with the electric/charging system of your car. If the alternator is faulty and overcharging the battery, it may cause the battery to lose its charge faster than it should. Have a certified technician, like one from YourMechanic, come and complete an inspection of the electric system in order to properly diagnose your problem and make the necessary repair.

ANSWER : This may be a sign of a failing voltage regulator or potentially a bad grounding problem causing a draw on the system. The voltage regulator is a unit that regulates the charging of the battery by the alternator. Often times this will result in the alternator allowing too much power to be delivered to the battery resulting in damaging wires and prematurely sometimes destroying the battery. In other cases it may result in the alternator not supplying enough power to the battery, resulting in undercharging the battery or not charging it at all. In either case, I would recommend having an expert from YourMechanic come to your location to diagnose your vehicle’s charging system.

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 : 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 : 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.