Diagnostic Circuit Check - With TBI

1. With ignition on and engine off, observe ``Check Engine'' light.
2. If light does not illuminate, refer to ``No Check Engine Light.''
3. If light flashes, refer to ``Erratic or Intermittent Check Engine Light.'' If light flashes a Code 12, check circuit 451 for short to ground between connector terminal B and ECM. If circuit is satisfactory, replace ECM.
4. If ``Check Engine'' light illuminates and remains lit, ground diagnostic test terminal and proceed to step 5.
5. If Code 12 is displayed, proceed to step 6. If Code 12 is not displayed, refer to ``No Code 12.''
6. Record any additional stored codes and diagnose beginning with lowest code. If engine cranks and will not start, refer to ``Engine Cranks But Will Not Start.'' If no additional codes are displayed, refer to ``Field Service Mode Check.''