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Test NS-7A - Inspecting Fuel Pump

NOTE: For connector terminal identification, see CONNECTOR IDENTIFICATION  . For wiring diagram, see WIRING DIAGRAMS  at end of article.
  1. Using DRB-II, stop actuation test. Using DRB-II, actuate ASD relay. Touch fuel pump relay to check for operation. If fuel pump relay does not pulsate, perform TEST NS-7B  . If fuel pump relay pulsates, stop actuation test. Disconnect fuel pump relay. Turn ignition on. Place DRB-II in voltmeter mode. Probe Red wire (Pink/Yellow wire on Wrangler) in fuel pump relay connector.
  2. If voltage is 10 volts or less, repair Red wire (Pink/Yellow wire on Wrangler) for an open circuit to splice. Perform VERIFICATION TEST VER-1  . If voltage is greater than 10 volts, disconnect fuel pump harness connector. Reconnect fuel pump relay. Using DRB-II, actuate fuel system. Place DRB-II in voltmeter mode. Probe Dark Green/Red wire (Orange/Black wire on Wrangler) in fuel pump connector. If voltage is more than 10 volts, go to step 6).
  3. If voltage is 10 volts or less, turn ignition off. Disconnect fuel pump relay. Using a DVOM, check resistance between fuel pump relay connector Dark Green/Black wire (Orange/Black on Wrangler) and fuel pump connector Dark Green/Red wire (Orange/Black on Wrangler).
  4. If resistance is less than 10 ohms, replace fuel pump relay. Perform VERIFICATION TEST VER-1  . If resistance is 10 ohms or more (Cherokee or Comanche), go to next step. If resistance is 10 ohms or more, repair open between fuel pump relay connector Orange/Dark Blue wire (Orange/Black on Wrangler) and fuel pump connector Orange/Black wire. Perform VERIFICATION TEST VER-1  .
  5. Disconnect ballast resistor. Ballast resistor is located next to windshield washer fluid reservoir. Using a DVOM, measure resistance across ballast resistor. If resistance is 10 ohms or more, replace ballast resistor. Perform VERIFICATION TEST VER-1  . If resistance is less than 10 ohms, repair Dark Green/Black wire between fuel pump relay and fuel pump. Perform VERIFICATION TEST VER-1  .
  6. Using DRB-II, stop actuation test. Place DRB-II in ohmmeter mode. Probe Black wire (Tan/Black wire on Wrangler) in fuel pump connector. If resistance is less than 5 ohms, replace fuel pump. Perform VERIFICATION TEST VER-1  . If resistance is 5 ohms or more, repair Black wire (Tan/Black wire on Wrangler) wire for an open circuit to ground. Perform VERIFICATION TEST VER-1  .
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