Ground Circuits
WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 1990 Mitsubishi Van, 1990 Mitsubishi Sigma, 1990 Mitsubishi Pickup, 1990 Mitsubishi Montero, and 1990 Mitsubishi Mirage. However, it is still accessible from the selected car via links, so may be relevant.
- Turn ignition off. Using an ohmmeter, check for continuity between ground and ECU terminals No. 101 and 106 (except Precis) or terminals No. 5 and 10 (Precis). Resistance should be zero ohms. If resistance is not zero ohms, repair open circuit between ECU connector and ground.
- Connect voltmeter negative lead to ground. Connect positive lead to ECU ground terminals as in step 1). With vehicle running, voltmeter should indicate less than 1 volt. If voltmeter reading is greater than 1 volt, check for open, corrosion or loose connection in ground circuit.