KC3 - Attempt to Eliminate DTC 312

- Disconnect vacuum line on Secondary Air Injection Diverter (AIRD) valve and cap vacuum line.

- Key "OFF".

- Repeat Engine Running Self-Test and record service codes. Key ON Engine Running (KOER) Self-Test

- Is Code 312 present?

Yes -- Electronic Engine Controls (EEC) system OK. Refer to Emission Control Systems/Testing and Inspection.

No -- Go to KC5. KC5 - Enter Output State Diagnostic Test Mode