Code 14 Igniter signal to ECU missing
 

what would can be done to resolve this kind of problem for my Toyota corolla with 5a engine

Here is a step by step diagnostic flow chart for the 3VZ motor, it will be similar to your Corolla.

http://htftp.offroadsz.com/marinhake...86troubles.pdf

Most of us are more familiar with Tacos and Runners and have access to those specific wiring diagrams and repair charts so you'll have to bear with us as this is slightly outside of our normal realm.