Code 86 - Analog/Digital Error (3.4L "F" Body): Notes

If any other codes are present, use those charts first. The Analog/Digital (A/D) multiplexer chip is an internal part of the ECM. Some ECM sensor inputs lead to the A/D multiplexer. If any one of them shorts to battery voltage for more than 15 seconds, the A/D error diagnostic code will set, resulting in a Code 86.