Use a high-impedance digital multimeter (>10k ohm/V) to avoid damaging the sensitive ECU internal circuits .
: Ensure the ECU casing and the E1/E01 pins have solid continuity to the chassis, as poor grounding is a common cause of erratic idling. wiring diagram daihatsu l9 ecu pinout
Main ECU power supply from the EFI relay, active when the ignition is ON. BATT: Constant battery backup power for memory. E1 / E01 / E02: Primary engine grounds. Sensor Inputs: PIM: Intake manifold pressure (MAP sensor) signal. THW: Engine coolant temperature (ECT) sensor signal. THA: Intake air temperature (IAT) sensor signal. VTA / VTHO: Throttle position sensor (TPS) signal. SPD: Vehicle speed sensor (VSS) signal. Actuator Outputs: #10, #20, #30: Fuel injector triggers. IGT1, IGT2, IGT3: Ignition timing signals for the coils. FC / FC1: Fuel pump relay control. W: Check Engine Light (CEL/MIL) output. Wiring Harness Color Codes (L9 JBDET Example) Use a high-impedance digital multimeter (>10k ohm/V) to
For detailed schematics of specific sub-systems like the or A/C , you can refer to specialized Daihatsu Service Manuals or Workshop Guides . BATT: Constant battery backup power for memory