FG10 - Check Octane Adjust Circuit For A Short to Ground

- 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 OCT ADJ circuit at the in-line connector and Test Pins 51, 91 and 103 at the breakout box.

- Is each resistance greater than 10,000 ohms?

YES -- Go to FG11. FG11 - Check PCM Integrity

NO -- SERVICE short circuit. REMOVE breakout box. If spark knock is still present, RETURN to Symptom Flowcharts. Testing and Inspection