Test J: No Communication With Natural Gas Vehicle Module
WARNING: This page is about a different car, the 2002 Ford Econoline. However, it is still accessible from the selected car via links, so may be relevant.
- Turn ignition switch to LOCK position. Disconnect Natural Gas Vehicle (NGV) module 60-pin harness connector C1009. NGV module is located on left inner fender well, behind coolant recovery bottle. Measure voltage between ground and NGV module 60-pin harness connector C1009 terminal No. 1 (Yellow wire). See Fig 1. If voltage is more than 10 volts, go to step 5. If voltage is 10 volts or less, go to next step.
- Remove Battery Junction Box (BJB) fuse No. 25 (20-amp). See Figure. Measure resistance between ground and NGV module 60-pin harness connector C1009 terminal No. 1 (Yellow wire). If resistance is 10 k/ohms or more, go to next step. If resistance is less than 10 k/ohms, repair short to ground in Yellow/Black wire. See WIRING DIAGRAMS . Retest system operation.
- Measure voltage between ground and Battery Junction Box (BJB) fuse No. 25 (20-amp) input terminal (Yellow wire). Fuse No. 25 input terminal is terminal closest to fuse No. 27. See Figure. If voltage is more than 10 volts, go to next step. If voltage is 10 volts or less, repair open in Yellow wire between BJB fuse No. 25 input terminal and starter motor relay. Starter motor relay is located in right front corner of engine compartment, near battery. See POWER DISTRIBUTION in SYSTEM WIRING DIAGRAMS article in ELECTRICAL. Retest system operation.
- Measure resistance in Yellow wire between NGV module 60-pin harness connector C1009 terminal No. 1 and fuse No. 25 (20-amp) output terminal (terminal furthest from fuse No. 27). See Figure and Fig 1 . If resistance is less than 5 ohms, replace fuse No. 25 (20-amp). Retest system operation. If resistance is 5 ohms or more, repair open in Yellow wire between fuse No. 25 output terminal and NGV module 60-pin harness connector C1009 terminal No. 1. See WIRING DIAGRAMS . Retest system operation.
- Turn ignition switch to ON position. Measure voltage between ground and NGV module 60-pin harness connector C1009 terminals No. 37 and 57 (Red wires) individually. If voltage is 10 volts or more at both terminals, go to next step. If voltage is less than 10 volts at either terminal, repair Red wire(s) as necessary. See WIRING DIAGRAMS . Retest system operation.
- Turn ignition switch to LOCK position. Measure resistance between ground and NGV module 60-pin harness connector C1009 terminals No. 40 and 60 (Black wires) individually. If both resistances are less than 5 ohms, diagnose NGV module communications problem. See appropriate MODULE COMMUNICATIONS NETWORK - ECONOLINE article. If resistance is more than 5 ohms at either terminal, repair open in Black wire(s). See WIRING DIAGRAMS . Retest system operation.