2005 echo battery problem

your problem not the car problem
you seldom use the car, and the battery discharge due to the alarm,anti theft or immobilizer system always on , clock etc.,and you drive a short distance, your battery have not fully charge and then you switch the engine off. How can the battery start for you.
Toyota diagnostic correctly, they explained in detail.You should start the engine and drive, and let the alternator charge battery. otherwise you should jump start if you continueous 2 times per month with this driving habbit or style.
Even you change a large size battery capacity 45AH to 60AH, same result No Start.
Same happening in show room, the demo car always battery discharge, dut to opening the door and light on dash with ign on, switch on someting to show the customer, so show room car always have the extra 12 v battery charger under the demo car 24 hr charge the car battery.
You better buy a charger or booster.

2007-01-06 14:56:19 補充：
Q: did you have the remote to open the door lock and did it operate with the alarm , your car indicator lamp flash when aim or un-aim the alarm.

I seen that you said you can leave the car for 4 months, then the car still can start???
For example:
1. Your car have alarm system, every hour use around 0.1A battery.
2. The battery for pavite car, usually 45 - 60A
3. 0.1A x 24 = 2.4A per day, less then 30 days, all the battery will gone.

How come you can start the car after 4 months, have you disconnect the battery cable?

I have experence park the car in South Africa, I have disconnect the Negative Cable, after 2.5 months I back from HK, it still can start when connect back the cable.