Test D: Powertrain Control Module Does Not Respond To Scan Tool
- Turn ignition switch to LOCK position. Disconnect NGS tester. Disconnect PCM harness connector C421. Inspect connector for loose, damaged or corroded terminals. If connector is okay, go to next step. If connector is damaged, repair connector as necessary. Check system for normal operation.
- Measure resistance between terminal No. 16 (Gray wire) at PCM connector and terminal No. 2 (Gray wire without ABS; Gray/Violet wire with ABS) at DLC. See Figure
and Fig 1
. If resistance is less than 5 ohms, go to next step. If resistance is not less than 5 ohms, repair open in Gray wire or Gray/Violet wire between DLC and PCM. Check system for normal operation.
- Measure resistance between terminal No. 15 (Blue wire) at PCM harness connector C421 and terminal No. 10 (Blue wire without ABS; Blue/White wire with ABS) at DLC. If resistance is less than 5 ohms, go to next step. If resistance is not less than 5 ohms, repair open in Blue wire or Blue/White wire. Check system for normal operation.
- Measure resistance in White/Blue wire between terminal No. 13 at PCM connector and terminal No. 13 at DLC. If resistance is less than 5 ohms, replace PCM. If resistance is not less than 5 ohms, repair open in White/Blue wire. Check system for normal operation.
Courtesy of FORD MOTOR CO.