Because both ISG and Non ISG control map is inputted in one type of ECM and selecting option is possible, one type is applied to both ISG and Non ISG option.

When ECM is installed to vehicle, ISG and Non ISG recognition is performed by ECM automatically as checking whether ground line(ECM connector is grounded or opened.(ISG and Non ISG recognition is performed every IG KEY ON process.)

If ISG, Non ISG recognition is not fulfilled well or any error occurs during the process, engine power generation is not sufficient.

ISG : ECM connector EUD-KB #76 terminal is grounded

Non ISG : ECM connector EUD-KB #76 terminal is opened(no wiring exists)

P1815 is set when recognized ESP data based on ECM CUD-K terminal 19 state(grounded or opened) is not readable or writable at EEP ROM. This code is due to ECM failure.