Test NS-5A - Inspecting Fuel Pump
WARNING: This page is about a different car, the 1995 Jeep Grand Cherokee. However, it is still accessible from the selected car via links, so may be relevant.
NOTE:
For circuit and connector terminal identification, see CONNECTOR IDENTIFICATION
in this article. For wiring diagram, see WIRING DIAGRAMS
section at the end of this article.
- Using scan tool, stop actuation test. Using scan tool, actuate Auto Shutdown (ASD) relay. Touch fuel pump relay. If fuel pump relay does not pulsate when actuated, go to TEST NS-5B . If fuel pump relay pulsates when actuated, turn ignition off.
- Remove fuel pump relay. Using scan tool in voltmeter mode, check voltage on fuel pump relay connector, fused battery voltage circuit (Red wire). If voltage is less than 10 volts, repair open Red wire or Red/White wire. Perform TEST VER-1 . If voltage is more than 10 volts, install a known good relay. Attempt to start engine. If engine starts, replace original relay. Perform TEST VER-1 .
- If engine does not start, reinstall original fuel pump relay. Disconnect fuel pump harness connector. Ensure fuel pump connector has clean and tight connections. Turn ignition on. Using scan tool, actuate fuel system. While still actuating, check voltage on fuel pump connector, fuel pump relay output circuit (Orange/Black wire) using scan tool in voltmeter mode. If voltage is less than 10 volts, repair open Dark Green/Black wire or Orange/Black wire. Perform TEST VER-1 . If voltage is more than 10 volts, stop actuation test.
- Turn ignition off. Using scan tool in ohmmeter mode, check resistance of fuel pump connector, fuel pump ground circuit (Black wire). If resistance is more than 5 ohms, repair open Black wire. Perform TEST VER-1 . If resistance is less than 5 ohms, replace fuel pump. Perform TEST VER-1 .