Input Displays: Notes
WARNING: This page is about a different car, the 1988 Cadillac Seville and 1988 Cadillac Eldorado. However, it is still accessible from the selected car via links, so may be relevant.
When trouble shooting a malfunction, the ECM input display can be used to determine if the switched inputs are properly interpreted. When one of the input tests is selected, the state of that device is displayed as "HI" or "LO". Basically, "HI" or "LO" represent the input terminal voltage for that circuit.
The display also indicates if the input changed state (activated or deactivated) since it was last tested. If a change occurred, an "X" will appear next to the "HI"/"LO" indicator. If a change did not occur, an "O" will remain displayed. The "X" will only appear once per selected input.
Input display may show Instrument Panel Cluster (IPC) trouble codes. The following is a brief summary of each ECM input.