Tools and Equipment
The DISplus/MoDIC as well as a reputable hand held multimeter can be used when testing inputs/components.
It is best to make the checks at the ECM connection, this method includes testing the wiring harness.
The correct Universal Adapter for the MS42/MS43 application should be used (#90 88 6 121 300). This will ensure the pin connectors and the harness will not be damaged.
When installing the Universal Adapter to the ECM (located below the windshield on the passenger side of the engine compartment), make sure the ignition is switched off.
NOTE:
NOTE for MS43: Allow at least 3 minutes to elapse after the key was set to the "OFF" position before disconnecting the ECM/TCM. This will allow sufficient time to complete the DM TL test. Voltage may be present (up to 3 minutes) causing damage to the ECM/TCM if they are disconnected during this time period (arcing).