Over the course of winter we didn’t drive the car for about 2-3 months. This car also has a Immobiliser and we need to use a remote switch communicate with the immobiliser before we can start the car. Press the switch then start the car.
Last year we replaced the battery with a brand new battery. and it was all fine. after 3 month of not driving, we realised the battery appears to be dead.
I used the multimeter ((set on 20v) to check the battery voltage, and it only showed as 1.5v.
I do understand a charged battery would need to be around 12.5-12.8, and when on around 14.5.
So next I decided to jump start the car, on my attempt, one i connected the terminals to start the dead car, I was not even able to see any lights upon inserting the car key in. I was not even able to communicate with the Immobiliser.
Basically nothing happened.
I while i had the car receiving charge from the running donor car, I check the voltage on the dead battery but the charge did not look it is increasing, although i did not wait that long and that might be why.
Before i bore you all my questions:
1- Could it be an issue with the Immobiliser draining the battery ?
2- Is it possible to remove the battery and put on charge overnight?
3- Given the battery is only 1.5 yr old, would I be able to revive it and use it, I keep reading about if the batteries are not used, the charge chemicals will turn into larger crystals making it harder to recharge.
Thank you for your patience and assistance in advance.