Engine does not start

First, let’s sort out the condition of the engine when it did not start.

• The fuel pump makes an operating noise.
• The meter unit works initially. (The tachometer comes and goes.)
• There is no sound of the cell motor turning. (it tries to turn but turns weakly.)

If I looked closely, I could see ‘Low Battery’ indicator on the meter unit…
“Battery gone?”

I tried it with more time, and it finally started on the third try.
However, the meter unit is displaying the following.

＜Fault codes and indications 1＞

○Er_1 42 and Er_3 42

I’m afraid that I don’t know what the fault code is.

＜Fault codes and indications 2＞

○(Water temperature) HIGH TEMP

The water temperature never gets hot when the engine is not running.
So, it could be a computer malfunction.

I would first suspect and confirm that the battery is under-voltage.

The battery is located under the seat, so first remove the seat.

＜Removing a seat＞

Insert the key, turn 90° clockwise and lift.

＜Check battery voltage＞

Check the battery voltage using a tester.
11.69 V is indicated.

This is low, but the voltage is higher than I thought.
For now, I decided to remove the battery and charge it.

＜Battery terminal disconnection 1＞

Remove the minus terminal using a socket (10 mm), then the plus terminal in turn.
This time, I somehow used a socket, but is it common to use a Phillips screwdriver (No.2)?

(To prevent shorting, a screwdriver with a plastic handle is better, surely…)

＜Battery terminal disconnection 2＞

Slide the removed terminals to the rear.

＜Battery disconnected 1＞

Remove the rubber band fixing the battery.
Pull the handle downwards to release the hooks and then pull it towards you.

＜Battery disconnected 2＞

Then the battery can be lifted off.

(It is narrow, so be careful not to rub your fingers on the tank cover or anything else to avoid peeling!)

＜Battery disconnected 3＞

But then, the drain hose on the right side got caught, so remove this one too.
The hose is just plugged in.

＜Battery fluid condition＞

I was surprised when I disconnected the battery.
The amount of battery fluid in all cells was below the lower limit.

＜Extract from inspection record＞

The inspection and maintenance record sent to me by the shop showed battery in the replacement parts column.
Why is the amount of battery fluid below the lower limit?
The battery fluid level was reduced in less than a month??

The battery capacity is likely to be insufficient if the battery is recharged as it is.
So, the battery fluid is topped up.

Followed by maintenance record ‘Charging the battery’.