Hi! I am a new owner of a Lexus RX 300. I am needing to charge my battery, and I am not sure which terminal is positive and which terminal is negative. I would really appreciate it if someone would please tell me which one is which. Thank you!!

 

The one on the left is Positive. If you look closely at the one on the right, on the battery near the terminal, you will see a (-) symbol stamped into the battery, hence the Negative terminal.

 

Thank you so much Ricco750!! 😊

 

Just a few safety pointers.
Note: Do not be tempted to break/complete the charging circuit near the battery. Make sure there is ample free movement of air to disperse hydrogen and oxygen as the battery is being charged.

1. Use protective eye wear.
2. Do not use open flame/spark near the battery .. specially when it is being charged.
3. Open the fill holes and make sure the [water + acid] level is above the plates inside. If you need to add, use distilled water.
4. Please follow this procedure to ensure no mishaps happen.
a) unplug the charger.
b) connect the + lead/clamp to the + terminal of the battery.
c) Find a metal ground post for the "-". I use the strut mounting nut or the bolt. Connect the "-" lead/clamp. You want this to be as far from the battery as it can be. This completes the charging circuit.
d) Set the charging level to appropriate or as low as possible [slow charge is best]. Now turn on/plug-in the charger.

On completion of charging follow these steps.
a) Turn off/un-plug the charger.
b) disconnect the "-" charging clamp.
c) disconnect the "+" charging clamp.


I used to trivialize the potential consequences of things going wrong till I experienced them first hand.

Salim

 

Thank you so much, salimshah!!

 

Impressed that you asked! Smart move Saves headaches later!

 

also understand that charging a battery may not "fix" it. It is best to test the battery with a tester, which puts a load on the battery. I have one of these: https://www.harborfreight.com/100a-6...AaAv71EALw_wcB

for extreme heat or cold environments, some batteries may only last 2 years.

 

Thank you so much, slothman! 😊

 

not a prob. also, some parts stores will test the battery and alternator free of charge.