Test V - Inertia Switch
- Key ON/Engine OFF Code 87 Displayed. Install fuel pressure gauge. Check if fuel pump runs. Cycle key from OFF to ON several times WITHOUT cranking engine. Pump should operate each time key ON occurs. If so, check fuel system for problems. If not, go to next step.
- Turn key OFF and wait 10 seconds. Disconnect 60-pin connector at ECA and inspect. Install breakout box and reconnect ECA. Turn key ON, leaving engine OFF. Set DVOM to 20 volt scale. Measure voltage between test pins 37 and 40 and between test pins 57 and 60. If either is less than 10.5 volts, go to test B. If both are 10.5 volts or more, go to next step.
- Turn key OFF and wait 10 seconds. Leave breakout box and ECA connected. Locate and disconnect fuel pump inertia switch. Set DVOM to 200 ohm scale and measure resistance of switch. If less than 5 ohms, go to next step. If 5 ohms or more, replace inertia switch and repeat QUICK TEST.
- Turn key ON, leaving engine OFF. Leave breakout box and ECA connected. Set DVOM to 20 volt scale. Measure voltage between chassis ground and power-to-pump(s) circuit at fuel pump inertia switch while cranking engine. If 8 volts or more during cranking, go to next step. If less than 8 volts during cranking, go to step 6).
- Turn key ON, leaving engine OFF. Leave breakout box and ECA connected. Set DVOM to 20 volt scale. Measure voltage between chassis ground and power-to-pump(s) circuit at fuel pump(s) while cranking. If 8 volts or more during cranking, service electric fuel pump(s). If less than 8 volts during cranking, repair open in power to pump(s) circuit and repeat QUICK TEST.
- Turn key ON, leaving engine OFF. Leave breakout box and ECA connected. Locate fuel pump relay. Set DVOM to 20 volt scale. Measure voltage between chassis ground and vehicle battery circuit at relay. If 10.5 volts or more, go to next step. If less than 10.5 volts, repair open in VPWR power circuit (between fuel pump relay and positive battery post) and repeat QUICK TEST.
- Turn key ON, leaving engine OFF. Leave breakout box and ECA connected. Locate fuel pump relay. Set DVOM to 20 volt scale. Measure voltage between chassis ground and vehicle power circuit at fuel pump relay. If 10.5 volts or more, go to next step. If less than 10.5 volts, repair open circuit (between fuel pump relay and ECA). Repeat QUICK TEST.
- Turn key OFF and wait 10 seconds. Leave breakout box and ECA connected. Disconnect fuel pump relay. With DVOM on 200 ohm scale, measure resistance between fuel pump circuit at pump relay and test pin 22. If less than 5 ohms, go to next step. If 5 ohms or more, repair open in fuel pump circuit. Repeat QUICK TEST.
- Turn key OFF. Leave breakout box installed and disconnect ECA. Disconnect fuel pump relay. With DVOM on 200,000 ohm scale, measure resistance between test pin 22 and test pins 40 and 60. If 10,000 ohms or more, go to next step. If less than 10,000 ohms, repair short in fuel pump circuit. Repeat QUICK TEST.
- Turn key OFF and wait 10 seconds. Leave breakout box installed. Leave fuel pump relay and ECA disconnected. With DVOM on 200,000 ohm scale, measure resistance between test pin 22 and test pins 37 and 57. If 10,000 ohms or more, reconnect fuel pump relay and go to next step. If less than 10,000 ohms, repair short to power in fuel pump circuit. Reconnect ECA and attempt to start engine. If engine does not start, replace ECA. Repeat QUICK TEST.
- Leave ECA disconnected. Connect jumper wire between test pin 22 and either test pin 40 or 60. With DVOM on 20 volt scale, turn key ON, leaving engine OFF. Turn key ON, leaving engine OFF. Measure voltage from chassis ground to power to pump(s) circuit at fuel pump relay. If 10.5 volts or more, replace ECA and repeat QUICK TEST. If less than 10.5 volts, replace fuel pump relay. Reconnect ECA and repeat QUICK TEST.