2003 Ford ZX2 AutomaticFACTORY OEM SERVICE PROCEDURE

Test K: No Module/Network Communications - SCP Network

WARNING: This page is about a different car, the 2002 Lincoln Navigator, 2002 Ford Expedition, 2001 Lincoln Navigator, and 2001 Ford Expedition. However, it is still accessible from the selected car via links, so may be relevant.
NOTE: After making any repair, perform data link diagnostic test. See DATA LINK DIAGNOSTIC TEST  under SELF-DIAGNOSTIC SYSTEM.
  1. Inspect New Generation Star (NGS) tester terminals for loose, damaged or corroded terminals. If problem does not exist with harness connector, go to next step. If problem exists with harness connector, repair as necessary.
  2. Turn ignition switch to LOCK position. Inspect Data Link Connector (DLC) terminals for loose, damaged or corroded terminals. Pay particular attention to terminals No. 2 (Tan/Orange wire) and No. 10 (Pink/Light Blue wire). See Figure. If problem does not exist with harness connector, go to next step. If problem exists with harness connector, repair as necessary.
  3. Disconnect Powertrain Control Module (PCM) harness connector. PCM is located on right side of engine compartment. Measure resistance in Tan/Orange wire between PCM harness connector C174 terminal No. 16 and DLC terminal No. 2. Measure resistance in Pink/Light Blue wire between PCM harness connector C174 terminal No. 15 and DLC terminal No. 10. If either resistances are more than 5 ohms, go to next step. If both resistances are 5 ohms or less, go to step  6.
  4. Disconnect and inspect 40-pin in-line harness connector C158. See Figure. If problem does not exist with harness connector, go to next step. If problem exists with harness connector, repair as necessary.
  5. Measure resistance in Tan/Orange wire between in-line harness connector C158 (female side) terminal No. 25 and DLC terminal No. 2. See Figure and Figure . Measure resistance in Pink/Light Blue wire between harness connector C158 (female side) terminal No. 29 and DLC terminal No. 10. If both resistances are 5 ohms or less, repair open in appropriate wire between PCM and in-line connector C158 (male side). If either resistance is more than 5 ohms, repair open in appropriate wire between DLC and in-line connector C158 (female side).
  6. Turn ignition switch to RUN position. Ensure PCM is still disconnected and perform data link diagnostic test. See DATA LINK DIAGNOSTIC TEST  under SELF-DIAGNOSTIC SYSTEM. If NGS tester does not indicate SYSTEM PASSED, go to next step. If NGS tester indicates SYSTEM PASSED, replace PCM. See POWERTRAIN CONTROL MODULE  under REMOVAL & INSTALLATION.
  7. If vehicle is not equipped with EATC, go to step  9. If vehicle is not equipped with EATC, connect PCM harness connector C174. Disconnect EATC module 13-pin harness connector C280. EATC is located behind center of instrument panel. Connector C280 only has one blank terminal. Measure resistance in Tan/Orange wire between EATC module harness connector C280 terminal No. 15 and DLC terminal No. 2. Measure resistance in Pink/Light Blue wire between EATC module harness connector C280 terminal No. 1 and DLC terminal No. 10. See Figure and Figure . If both resistances are 5 ohms or less, go to next step. If either resistance is more than 5 ohms, repair open in appropriate wire.
  8. Turn ignition switch to RUN position. Ensure EATC is still disconnected and perform data link diagnostic test. See DATA LINK DIAGNOSTIC TEST  under SELF-DIAGNOSTIC SYSTEM. If NGS tester does not indicate SYSTEM PASSED, go to next step. If NGS tester indicates SYSTEM PASSED, replace EATC. See ELECTRONIC AUTOMATIC TEMPERATURE CONTROL MODULE  under REMOVAL & INSTALLATION.
  9. If vehicle is equipped with EATC, connect EATC harness connector. On all vehicles, disconnect instrument cluster White 22-pin harness connector C237. Measure resistance in Tan/Orange wire between instrument cluster harness connector C237 terminal No. 1 and DLC terminal No. 2. Measure resistance in Pink/Light Blue wire between instrument cluster harness connector C237 terminal No. 2 and DLC terminal No. 10. See Figure and Figure If both resistances are 5 ohms or less, go to next step. If either resistance is more than 5 ohms, repair open in appropriate wire.
  10. Turn ignition switch to RUN position. Ensure instrument cluster is still disconnected and perform data link diagnostic test. See DATA LINK DIAGNOSTIC TEST  under SELF-DIAGNOSTIC SYSTEM. If NGS tester does not indicate SYSTEM PASSED, connect all previously disconnected harness connectors, clear all diagnostic trouble codes and repeat data link diagnostic test. See DATA LINK DIAGNOSTIC TEST  under SELF-DIAGNOSTIC SYSTEM. If NGS tester indicates SYSTEM PASSED, replace instrument cluster. See INSTRUMENT CLUSTER  under REMOVAL & INSTALLATION.
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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.

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