Test C: Pcm & Abs/TC Module Not Responding To Scan Tool

Check DTC

Perform DATA LINK DIAGNOSTICS. If DTC 0003 or 0007 is retrieved for both circuit No. 914 and 915, go to step 3). Otherwise go to next step.

Identify Circuit

If DTC 0003 or 0007 is retrieved only for circuit No. 914, go to step 10). Otherwise go to step 6).

Check DLC

Inspect DLC terminals for damage and corrosion. Repair as necessary. If connector terminals are okay, go to next step.

Check For Short Between Circuit No. 914 & 915

Measure resistance between DLC terminals No. 2 and 10. See Figure. If resistance is 5 ohms or less, go to step 14). If resistance is greater than 5 ohms, go to next step.

Check Circuit No. 914 & 915 For Open

Turn ignition off. Disconnect PCM. Measure resistance of circuit No. 914 (Tan/Orange wire) between DLC terminal No. 2 and PCM harness connector terminal No. 16. See Figure. Measure resistance of circuit No. 915 (Pink/Light Blue wire) between DLC terminal No. 10 and PCM harness connector terminal No. 15. If either measurement is greater than 5 ohms, repair open Tan/Orange or Pink/Light Blue wire. If both resistance measurements are less than 5 ohms, verify scan tool is okay and repeat Data Link Diagnostics.

Check DLC Terminal No. 2

Inspect DLC terminal No. 2 for damage and corrosion. See Figure. Repair as necessary. If connector terminals are okay, go to nex t step.

Check Circuit No. 914 For Open

Turn ignition off. Disconnect PCM. Measure resistance of circuit No. 914 (Tan/Orange wire) between DLC terminal No. 2 and PCM harness connector terminal No. 16. If resistance measurement is greater than 5 ohms, repair open Tan/Orange wire. If resistance measurement is less than 5 ohms, go to next step.

Check Circuit No. 914 For Short To Ground

Measure voltage between DLC terminals No. 2 and 5. If voltage does not exist, go to step 14). If voltage exists, go to next step.

Check Circuit No. 914 For Short To Power

Measure voltage between DLC terminals No. 2 and 16. If voltage does not exist, go to step 14). If voltage exists, check scan tool operation.

Check DLC Terminal No. 10

Inspect DLC terminal No. 10 for damage and corrosion. Repair as necessary. If connector terminals are okay, go to next step.

Check Circuit No. 915 For Open

Turn ignition off. Disconnect PCM. Measure resistance of circuit No. 915 (Pink/Light Blue wire) between DLC terminal No. 10 and PCM harness connector terminal No. 15. If resistance measurement is greater than 5 ohms, repair open Pink/Light Blue wire. If resistance measurement is less than 5 ohms, go to next step.

Check Circuit No. 915 For Short To Ground

Measure voltage between DLC terminals No. 10 and 5. If voltage does not exist, go to step 14). If voltage exists, go to next step.

Check Circuit No. 915 For Short To Power

Measure voltage between DLC terminals No. 2 and 16. If voltage does not exist, go to next step. If voltage exists, check scan tool operation.

Check For Short At Connector C100

Disconnect harness connector C100. See Fig 1. Perform Data Link Diagnostics. If DTC 0001 is retrieved, go to next step. If DTC 0001 is not retrieved, go to step 16).

Check For Short At PCM

Reconnect harness connector C100. Disconnect PCM harness connector. Perform Data Link Diagnostics. If DTC 0001 is retrieved, replace PCM. Repeat DATA LINK DIAGNOSTICS under COMMUNICATIONS NETWORK DIAGNOSTICS to confirm repair.

Check For Short At ABS/TC Module

Restore all electrical connections. Disconnect Anti-lock Brake/Traction Control (ABS/TC) module. Perform Data Link Diagnostics. If DTC 0002 is retrieved, replace ABS/TC module. Repeat DATA LINK DIAGNOSTICS under COMMUNICATION NETWORK DIAGNOSTICS to confirm repair. If DTC 0002 is not retrieved, repair/replace twisted wire pair (Tan/Orange wire and Pink/Light Blue wire) between DLC and ABS/TC module connector. Restore electrical connections and repeat DATA LINK DIAGNOSTICS under COMMUNICATION NETWORK DIAGNOSTICS to confirm repair.

Fig 1: Identifying Harness Connector C100 Terminals

Courtesy of FORD MOTOR CO.