Buying exact price for petrol

Have you wonder how to pump in exact amount of petrol if you are paying by credit/debit card. I sometime try to play with the fuel nozzle but can never get exact amount. Below what i learn how to do it after messing around with the panel.

1. Insert your customer loyalty card in slot (A)
2. Take out your customer loyalty card once prompt by display.
3. Insert your credit/debit card in slot (A)
4. Take out your credit/debit card once prompt by display.
5. Wait for the confirmation to start fill up fuel displayed on the screen, DO NOT pick up the nozzle yet.
6. Press the preset at (B). You can choose RM10,RM20,RM30, RM40 or RM50.
7. Pick up the nozzle and start filling your car. You can lock the nozzle lever and let your hand free to do other things. (clean windshield, take out rubbish,etc). Use common sense. Do not leave your car unattended. The pump will stop pumping at value you select in step 6.

Background story. This what happen when you're paying fuel by credit/debit card at fuel pump kiosk.
a) Once you insert your credit card in step 3, the machine will check your credit/debit card. If you have enough balance, it will charge you RM150.00-RM200.00 as pre paid.
b) Once you finish pumping fuel, the machine will return the excess amount to your credit/debit card. Example: If machine charge you RM200.00 in step 3, it will return back RM150.00 if you fill in RM50.00 in step 6.
I can see this transaction in my Maybank2u onlne statement. I'm not sure about other bank.


Note:
Above step mostly work with Shell fuel pump. Other brand fuel station will require slightly different steps. I leave it to you all to try it out.