Test B: Engine Does Not Crank & Relay Does Not Click (7.3L)
WARNING: This page is about a different car, the 2003 Ford Pickup, 2003 Ford F550 Super Duty, 2003 Ford F450 Super Duty, and 2003 Ford Excursion. However, it is still accessible from the selected car via links, so may be relevant.
- Check Tan/Red Wire For Voltage
Disconnect starter motor relay. Turn ignition switch to START position. Measure the voltage between the starter motor relay connector terminal No. 86 (Tan/Red wire) and ground while holding the key in the START position. See Figure. Is the voltage greater than 10 volts? If yes, go to step 10. If no, for A/T, go to next step. For M/T, go to step 5. - Check White/Pink Wire For Voltage At The DTR Sensor
Turn ignition off. Disconnect Digital Transmission Range (DTR) sensor connector. Turn ignition switch to START position. Measure the voltage between the DTR sensor connector terminal No. 10 (White/Pink wire) and ground while holding the ignition switch in the START position. See Fig 1. Is the voltage greater than 10 volts? If yes, go to next step. If no, go to step 7. - Check Tan/Red Wire For Open
Turn ignition off. Measure the resistance between the DTR sensor connector terminal No. 12 (Tan/Red wire) and the starter motor relay connector terminal No. 86. See Figure and Fig 1 . Is the resistance less than 5 ohms? If yes, go to next step. If no, repair Tan/Red wire between DTR sensor and starter motor relay. See WIRING DIAGRAMS . Test the system for normal operation. - Check Digital Transmission Range (DTR) Sensor Adjustment
Perform the DTR sensor adjustment. See DIGITAL TRANSMISSION RANGE SENSOR (7.3L) under ADJUSTMENTS. Is the DTR sensor adjusted correctly? If yes, install a new DTR sensor. See DIGITAL TRANSMISSION RANGE (DTR) SENSOR under REMOVAL & INSTALLATION. Test the system for normal operation. If no, adjust DTR sensor as necessary. Test the system for normal operation. - Check White/Pink Wire For Voltage At The Clutch Switch Or Jumper
Turn ignition off. Disconnect clutch pedal switch connector. Turn ignition switch to START position. Measure the voltage between the clutch pedal switch connector terminal No. 1 (White/Pink wire) and ground while holding the key in the START position. See Fig 2. Is the voltage greater than 10 volts? If yes, go to next step. If no, go to step 7. - Check Tan/Red Wire For Open
Turn ignition off. Measure the resistance between the clutch pedal switch connector terminal No. 2 (Tan/Red wire) and the starter motor relay connector terminal No. 86. See Figure and Fig 2 . Is the resistance less than 5 ohms? If yes, install a new clutch pedal switch. See CLUTCH PEDAL POSITION (CPP) SWITCH under REMOVAL & INSTALLATION. Test the system for normal operation. If no, repair Tan/Red wire between clutch pedal switch and starter motor relay. See WIRING DIAGRAMS . Test the system for normal operation. - Check For Voltage At Fuse No. 31
Turn ignition off. Disconnect fuse No. 31 (15-amp). Turn ignition switch to start position. Measure the voltage between fuse No. 31 (Dark Green wire) in the central junction box and ground while holding the key in the START position. See Figure. Is the voltage greater than 10 volts? If yes, repair White/Pink wire or Light Blue/Yellow wire between central junction box and clutch pedal switch. See WIRING DIAGRAMS . Test the system for normal operation. If no, go to next step. - Check Light Green/Violet Wire For Voltage
Turn ignition off. Disconnect ignition switch connector. Measure the voltage between the ignition switch connector terminal B4 (Light Green/Violet wire) and ground. See Fig 3. Is the voltage greater than 10 volts? If yes, go to next step. If no, check fuse No. 103 (50-amp) in central junction box. See Figure. If fuse is okay, repair Light Green/Violet wire between central junction box and ignition switch. See WIRING DIAGRAMS . Test the system for normal operation. - Check The Ignition Switch
Perform the ignition switch component test. See appropriate STEERING COLUMN SWITCHES article in ACCESSORIES & EQUIPMENT. Does the ignition switch test good? If yes, repair Dark Green wire between central junction box and ignition switch. Test the system for normal operation. If no, install a new ignition switch. See appropriate STEERING COLUMN SWITCHES article in ACCESSORIES & EQUIPMENT. Test the system for normal operation. - Check Black Wire For Open
Turn ignition off. Measure the resistance between the starter motor relay connector terminal No. 85 (Black wire) and ground. See Figure. Is the resistance less than 5 ohms? If yes, install a new starter motor relay. Test the system for normal operation. If no, repair Black wire between starter relay and ground. See WIRING DIAGRAMS . Test the system for normal operation.