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Q: Battery gets drained, recharging the battery

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I haven't been driving my car much and it has only 32,000 miles on it. I've been having problems with the battery getting drained, probably because the car sits too long. I've read in the manual that it's not recommended to get it recharged while it's in the car, but there are remote terminals for jumpstart, located in the trunk. Are they safe to use for battery recharge? The battery is very hard to get out, so can I use the terminals that are in the trunk and not get the battery out?

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.

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