Some components remain On and my battery drains overnight?

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 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 there:

If you’re in the process of trying to diagnose a battery draining issue, it’s best for you to start with the ignition switch; as a faulty switch is commonly the component that causes most battery draining issues. If the ignition switch ends up being good, contact one of our mobile mechanics and we’ll complete a battery will not hold a charge inspection to pinpoint the source of your issues.

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, 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 : 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 : 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 : Even though you did disconnect the battery, thus preventing any "external" current flow overnight, you still should check for parasitic current draw from the vehicle’s electrical system, that is a current flow of (roughly) 50 or more milliamps when the car is "off". It’s also possible there is parasitic (unintended) current draw even while the car runs and if it is of a magnitude that the charging system just can’t keep up with that could slowly, or eventually, leave your battery in a discharged state. There could be an intermittent fault in the charging circuit but normally if the alternator was dropping out, the charge/battery warning light would come on and alert you. There are two things to do at once: check the output of the charging system (have a certified mechanic do it) per the Factory Service Manual protocol and, two, take the battery to a professional battery store, have it fully charged, and then have them run a load test on the battery (load tests can’t be done on discharged batteries). If, say, you find that there is nothing wrong with the battery and vehicle charging output is normal, then clearly there is a problem in your car’s electrical system, possibly including unwanted (parasitic) power draw but possibly ALSO including a circumstance where a faulty starter draws too much current, thus rendering it inoperable unless the battery is practically brand new (battery CCA slowly degrades over time and although a new battery will run a weak starter, an "older" battery might not). The point is you could have a "combination" of problems. If you are electing to have a certified mechanic take care of this from top to bottom (perform all the tests and the obviously needed repair) simply request an electrical component malfunction diagnostic and the responding mechanic will get this resolved for you pronto. Please don’t hesitate to inquire if you have additional concerns.