Pulling Codes From Your 240sx ECU
SOHC Ka24e Codes
The ECU modes
The electronic control unit have five mode:
Mode I- Exhaust gas sensor monitor (Normal mode)
Mode II- Mixture ratio feedback control monitor
Mode III- Self-diagnostic
Mode IV- Switch on/off diagnostic system
Mode V- Real-time diagnostics system.
The unit automatically return to normal mode I when the ignition is switched off.
Only mode III will be studied here. Troubles code are stored on mode III. The stored codes will be lost if the car battery is disconnected or if after selecting mode III, mode IV is selected.