FG4 - Check Continuity of Octane Adjust Circuit

NOTE: There should be continuity from OCT ADJ circuit through the in-line connector and shorting bar to SIG RTN circuit.

- Key Off.

- Disconnect Powertrain Control Module (PCM). Inspect for damaged or pushed out pins, corrosion, loose wires, etc. Service as necessary.

- Install breakout box, leave PCM disconnected.

- Measure resistance between Test Pin 91 and OCT ADJ Test Pin 30 at the breakout box.

- Is the resistance less than 5.0 ohms?

YES -- REPLACE PCM. REMOVE breakout box. Rerun quick test. Diagnostic Subroutines (DSR) - Extracting Codes

NO -- SERVICE open OCT ADJ circuit or shorting bar or SIG RTN circuit. REMOVE breakout box. Rerun quick test. Diagnostic Subroutines (DSR) - Extracting Codes