ppl ,
I need help.

I have accord 90 model. It fails to start when the climate is hot (around 80F), which means the car's interior is hot too..But if i try starting the car at night it starts w/o any trouble...

few indication.. i have observed.

1. the battery indicator keep blinking sometimes.
2. and when i try starting, the car shivers sometimes.

any help will be appreciated

I have replaced many main relays for the heat issue your discribing.This is located inside the car. When the sun is out is when this is a big problem due too the high heat inside the car. The relay has a small circuit board inside and the solder cracks and pulls away in the heat. This is located on the left side underneath the dash. You can either replace it or resolder the connections.
Hope this helps!

if that isn't it the other educated guess is the Engine Coolant Temperature Sensor (ECTS) .. i've seen this and main relay.. but i'd try main relay first.