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Test E: Natural Gas Vehicle Module (NGVM) Does Not Respond To NGS

  1. Turn ignition off. Disconnect NGVM connector located left side of engine compartment, on inner fender. Inspect connector for loose, damaged or corroded terminals. Repair connector as necessary and retest system for normal operation. If connector is okay, go to next step.
  2. Using an ohmmeter, measure resistance of Tan/Orange wire between terminal No. 19 at NGVM connector and terminal No. 2 at Data Link Connector (DLC). See Figure and Fig 1 . Also, measure resistance of Pink/Light Blue wire between terminal No. 18 at NGVM connector and terminal No. 10 at DLC. If both resistance readings are less than 5 ohms, replace NGVM and retest system for normal operation. If any resistance reading is 5 ohms or more, go to next step.
  3. Disconnect Natural 76-pin connector C234 located on driver's side of engine compartment on firewall. Inspect connector for loose, damaged or corroded terminals. Repair connector as necessary and retest system for normal operation. If connector is okay, go to next step.
  4. Measure resistance of Tan/Orange wire between terminal No. 61 at female half of connector C234 and terminal No. 2 at DLC. See Figure and Figure . Also, measure resistance of Pink/Light Blue wire between terminal No. 59 at female half of connector C234 and terminal No. 10 at DLC. If both resistance readings are less than 5 ohms, repair open Tan/Orange wire and/or Pink/Light Blue wire between NGVM connector and male half of connector C234. Retest system for normal operation. If any resistance reading is 5 ohms or more, repair open Tan/Orange wire and/or Pink/Light Blue wire between female half of connector C234 and DLC. Retest system for normal operation.
Fig 1: Identifying NGVM Connector Terminals
G98C01717Courtesy of FORD MOTOR CO.