Test E: ECM Signal Test

1 . With Ignition Switch in RUN, press the SET and SYSTEMS CHECK buttons on the Driver Information Center/Electronic Compass Display at the same time. The Display will show: AABB CDE. Observe position "E". The display should show an "S".
^ If an "S" is present, check for a poor connection. If OK, replace the Driver Information Center/Electronic Compass Display
^ If an "X' is present go to step 2.

2. Connect a bi-directional scan tool to the ALDL connector and attempt to read any engine data such as engine RPM.
^ If data is present, check ORN (461) wire for an open. If OK, check for a poor connection. If OK, replace the Driver Information Center/ Electronic Compass Display.
^ If scan tool indicates no data, check the ORN (461) wire for an open or short to ground. Check that the Driver Information Center/Electronic Compass Display is not grounding the ORN (461) wire. If OK, refer to ECM diagnosis.