Stupid question about dead car battery (car wouldn't start)

**Walter** · February 15th, 2018 11:52 AM

Avoid attaching charger directly to the negative terminal ... clamp it on any exposed metal in the engine ...

**dr. d** · February 15th, 2018 12:47 PM

Originally Posted by Walter

Avoid attaching charger directly to the negative terminal ... clamp it on any exposed metal in the engine ...

bakit daw, po?
kasi, that terminal is usually the most convenient place to clamp it on.

**12vdc** · February 15th, 2018 02:31 PM

Originally Posted by kisshmet

Negative terminal shouldnt be disconnected because its always connected to the ground and the body of all cars are good ground. Should the new gadget you have bought is defective or shorted the ground or the body of your car is a good place to absorb the high current that could flow

In Automotive tech practice, it is always the negative terminal of the battery that should be disconnected to isolate the common ground(-). The explanation is that chassis of the car being negative potential has the widest area and risk of accidentally shorting positive to the common ground will be less if the negative potential from the battery is removed(ie accidentally dropping a live positive lead of an accessory to the chassis or any part of the body).

Those smart chargers can detect any short or low internal resistance inside the battery and they automatically shut or give error message if such errors are detected.

**12vdc** · February 15th, 2018 02:43 PM

Originally Posted by baludoy

I finally Tried it yesterday [emoji4]

pag pumapalo na ng 0 (intermittently) fully charged na iyong batt? Very unclead iyong manual about this

Yes it means the charger is not pumping current to the battery, or its on trickle charge mode.

The numbers you are seeing is the output current, the higher the larger current you could hear the fan RPM shoot up to cool down the charger during high current operation.

**red_one** · February 16th, 2018 12:37 AM

Originally Posted by baludoy

I finally Tried it yesterday [emoji4]

pag pumapalo na ng 0 (intermittently) fully charged na iyong batt? Very unclead iyong manual about this

Ps pls excuse the dusty engine bay [emoji200]

Sent from my ASUS_Z00AD using Tapatalk

As already mentioned above, you better connect the negative clip to chassis or ground point or any exposed metal part.

If you look at the photo of my charger in previous post, the negative clip is connected to the engine hook (maybe it is dark so not clearly seen). Only the positive clip is connected to battery positive.

0 on the display means charging finished or battery full. You can now disconnect the charger.

Sent from my ASUS_X00DDA using Tapatalk

**Walter** · February 16th, 2018 07:50 AM

Originally Posted by dr. d

bakit daw, po?
kasi, that terminal is usually the most convenient place to clamp it on.

For safety reasons ... not really sure why ... it's just standard practice ...

**baludoy** · February 16th, 2018 10:55 AM

Thanks for the tips. Will do that next time

Sent from my ASUS_Z00AD using Tapatalk

**jick.cejoco** · February 16th, 2018 05:33 PM

Originally Posted by Walter

For safety reasons ... not really sure why ... it's just standard practice ...

Two reasons why:

1. To avoid Sparks near the battery specially if the battery is gassing- explosively flammable hydrogen gas,

2. So that if the battery fails to fully or efficiently charge, to force you to clean the battery post or connection.

**falken** · February 16th, 2018 10:10 PM

Originally Posted by jick.cejoco

Two reasons why:

1. To avoid Sparks near the battery specially if the battery is gassing- explosively flammable hydrogen gas,

2. So that if the battery fails to fully or efficiently charge, to force you to clean the battery post or connection.

I learned something again. Thanks!

Sent from my SM-T705 using Tapatalk

**Janemar** · February 16th, 2018 10:35 PM

Originally Posted by baludoy

Do i need to disconnect the battery in order to safely and effectively use this digital battery charger

is it safe to leave it on the engine bay while it's charging the car battery?

How long does it need to recharge the battery?

Sent from my ASUS_Z00AD using Tapatalk

Maki butt in lang since bored. LOL.

I see your car is monty/strada? So yes, you can directly hook up your charger sa batt without removing the terminals.

For newer cars with smart electrical system, be sure to clamp the charger positive clip to positive of battery terminal and negative clamp to a good body ground and not directly to battery (-) terminal. This is because the PCM/BCM is monitoring the state of charge of your battery real time, 24/7, and the usual position of the ammeter/load sensor is act negative terminal connector.

I can confirm 10th gen civic and new ford cars now have this system, not sure sa other brands.