GM OBD Trouble Code 86

Engine Control Module Analog/Digital Error

The Engine Control Module (ECM) monitors its internal circuitry for problems. These have been designated analog/digital faults.

Fault Code Description

86 - Engine Control Module Analog/Digital Error

Symptoms

• The Check Engine Light will illuminate when code 86 is present
  

Common Problems

• In most cases, an internal ECM fault has triggered the code 86. If that is the case, the EMC should be replaced.