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Test NS-9B - "No Sync Pick-Up Signal"

NOTE: For connector terminal identification, see CONNECTOR IDENTIFICATION  . For wiring diagram, see WIRING DIAGRAMS  at end of article.
  1. Ensure distributor shaft turns when engine is cranked. If shaft does not turn, repair as necessary. Perform VERIFICATION TEST VER-1  . If shaft turns, disconnect distributor sync pick-up sensor. Turn ignition on. Place DRB-II in voltmeter mode. Probe Tan/Yellow wire (Gray/Black wire on Wrangler) in distributor sync pick-up connector. If voltage is more than 4.5 volts, go to step 4).
  2. If voltage is 4.5 volts or less, turn ignition off. Disconnect engine controller 60-pin connector. Place DRB-II in ohmmeter mode. Probe Tan/Yellow wire (Gray/Black wire on Wrangler) in distributor sync pick-up connector. If resistance is less than 10 ohms, repair Tan/Yellow wire (Gray/Black wire on Wrangler) for a short to ground. Perform VERIFICATION TEST VER-1  .
  3. If resistance is 10 ohms or more, check Tan/Yellow wire (Gray/Black wire on Wrangler) for continuity between engine controller connector terminal No. 44 and distributor sync pick-up sensor connector using a DVOM. If resistance is less than 10 ohms, replace engine controller. Perform VERIFICATION TEST VER-1  . If resistance is 10 ohms or more, repair open Tan/Yellow wire (Gray/Black wire on Wrangler). Perform VERIFICATION TEST VER-1  .
  4. Probe Orange wire (White/Black wire on Wrangler) in distributor sync pick-up connector. If voltage is 7.5 volts or less (except Wrangler), go to step 6). If voltage is 7.5 volts or less (Wrangler), go to step 8). If voltage is greater than 7.5 volts (all models), go to next step.
  5. Turn ignition off. Place DRB-II in ohmmeter mode. Probe Black/Light Blue wire (Brown/Red wire on Wrangler) in distributor sync pick-up connector. If resistance is less than 10 ohms, replace distributor sync pick-up. Perform VERIFICATION TEST VER-1  . If resistance is 10 ohms or more, repair open Black/Light Blue wire (Brown/Red on Wrangler) between sensor connector and splice. Perform VERIFICATION TEST VER-1  .
  6. Turn ignition off. Disconnect engine controller 60-pin connector. Place DRB-II in ohmmeter mode. Probe engine controller connector terminal No. 7 Orange wire. If resistance is less than 10 ohms, repair Orange wire for a short to ground. Disconnect battery quick disconnect. Reconnect battery quick disconnect. Perform VERIFICATION TEST VER-1  .
  7. If resistance is 10 ohms or more, check Orange wire for continuity between engine controller connector terminal No. 7 and distributor sync pick-up sensor connector using a DVOM. If resistance measures less than 10 ohms, replace engine controller. Perform VERIFICATION TEST VER-1  . If resistance is 10 ohms or more, repair Orange wire between engine controller connector terminal No. 7 and distributor sync pick-up sensor connector. Perform VERIFICATION TEST VER-1  .
  8. Disconnect distance (speed) sensor. Place DRB-II in voltmeter mode. Probe Orange wire in distributor sync pick-up sensor connector. If voltage is greater than 7.5 volts, replace distance (speed) sensor. Perform VERIFICATION TEST VER-1  . If voltage is 7.5 volts or less, go to next step.
  9. Turn ignition off. Disconnect engine controller 60-pin connector. Check Orange wire for continuity between engine controller connector terminal No. 7 and distributor sync pick-up sensor connector using a DVOM. If resistance is less than 10 ohms, replace engine controller. Perform VERIFICATION TEST VER-1  . If resistance is 10 ohms or more, repair Orange wire between engine controller connector terminal No. 7 and distributor sync pick-up sensor connector. Perform VERIFICATION TEST VER-1  .
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