X21 - Check FC/LFC Circuit For Short to Ground

- Key Off.

- Disconnect Scan Tool from DLC.

- Disconnect PCM. Inspect for damaged or pushed out pins, corrosion, loose wires, etc. Service as necessary.

- Install breakout box, leave PCM disconnected.

- Disconnect CCRM.

- Measure resistance between Test Pin 68 (LFC) and Test Pins 51,103 (PWR GND) and 91 (SIG RTN) at the breakout box.

- Is each resistance greater than 10,000 ohms?

YES -- GO to X22. X22 - Check Fan Running Mode

NO -- SERVICE short to ground in FC/LFC circuit. RECONNECT all components. Rerun quick test. Diagnostic Subroutines (DSR) - Extracting Codes