Inspection of ECM & Its Circuits: Notes
WARNING: This page is about a different car, the 2004 Suzuki XL-7 and 2004 Suzuki Grand Vitara. However, it is still accessible from the selected car via links, so may be relevant.
ECM and its circuits can be checked at ECM wiring couplers by measuring voltage, pulse signal and resistance.
CAUTION:
ECM cannot be checked by itself. It is strictly prohibited to connect voltmeter or ohmmeter to ECM with couplers disconnected from it.