TESTING

1.2L Engine

1. Using a stethoscope, ensure that a clicking sound is heard at each injector (when idling or cranking the engine).
2. Turn the ignition switch to the OFF position, then unfasten the control unit connector.
3. Measure the voltage between fuel injector connector terminal 1 and ground. Resistance should be 9 volts or above. If not, repair the fuel injector power circuit.
4. Measure resistance between the fuel injector connector terminals. Resistance should be as follows:
   • Terminals 1 and 2: 10–18 ohms
   • Terminals 1 and 3: 10–18 ohms
   • Terminals 1 and 4: 10–18 ohms
5. If resistance is not within specification, repair the engine harness. If the engine harness is good, replace the fuel injector.
6. Connect the fuel injector connector. Turn the ignition ON.
7. Measure the resistance between ECU connector terminals and ground. Resistance should be as follows:
   • Terminal 12 and ground: 8 volts or more
   • Terminal 25 and ground: 8 volts or more
   • Terminal 11 and ground: 8 volts or more
8. If not within specification, repair the harness connector between ECU and fuel injectors.
9. Turn the ignition OFF and disconnect the ECU connector.
10. Measure resistance between the ECU connector terminal and ground. Resistance should be as follows:
    • Terminal 13 and ground: below 10 mega-ohms
    • Terminal 26 and ground: below 10 mega-ohms
11. If not within specification, repair the harness connector between the ECU and ground.

1.8L Engine

1. Using a stethoscope, ensure that a clicking sound is heard at each injector (when idling or cranking the engine).
2. Turn the ignition switch to the OFF position, then disconnect the control unit connector.
3. Using a voltmeter, measure voltage between ground and terminals 49 (W), 50 (W), 51 (WR) (WL on XT models), and 52 (WR) (WL on XT models) on the control unit connector.
4. The voltmeter should read 12 volts at all terminals.
   1. If the voltmeter reads below 10 volts in any line, the harness from the battery to the control unit through the resistor and injector is broken or shorted.
5. Disconnect each fuel injector electrical connector.
6. Using an ohmmeter, measure resistance between the terminals of each injector. The ohmmeter should read 2–3 ohms at each injector. If the ohmmeter reads infinity, the circuit is broken. If the ohmmeter reads 0 ohms, the circuit is shorted. Replace the injector.
7. Using a voltmeter, measure voltage between the terminals of each injector connector and ground. The voltmeter should read 12 volts. If voltage obtained is less than 10 volts, the harness from the battery to the injector through the resistor is disconnected or shorted.
8. Disconnect the electrical harness from the resistor.
9. Using an ohmmeter, measure the resistance between terminals (W) and (B) of the resistor. The ohmmeter should read 5.8–6.5 ohms. If the reading are not as specified, replace the resistor.
10. Using a voltmeter, measure voltage between terminal 5 (R) of the body harness connector and ground. The voltmeter should read 12 volts.

2.2L and 2.5L Engines

1. Using a stethoscope, ensure that a clicking sound is heard at each injector (when idling or cranking the engine).
2. Disconnect the fuel injector connector.
3. Measure the voltage between fuel injector connector terminal 2 and ground. Voltage should be 10 volts minimum. If not, repair the harness or connector.
4. Measure the resistance between the injector terminals. Resistance should be 10–12 ohms. If not, replace the fuel injector.
5. Fasten the fuel injector connector.
6. Measure the voltage between each fuel injector terminal of the ECU connector and ground. Resistance should be as follows:
   • Terminal 11 and ground: 10 volts minimum
   • Terminal 12 and ground: 10 volts minimum
   • Terminal 13 and ground: 10 volts minimum
   • Terminal 26 and ground: 10 volts minimum
7. If not within specification, repair the harness or connector.
8. Disconnect ECU connector.
9. Measure the resistance between ground and ECU connector terminals 24 and 25. Resistance should be 0 ohms, if not, repair the harness or connector.

2.7L Engine

1. Using a stethoscope, ensure that a clicking sound is heard at each injector (when idling or cranking the engine).
2. Disconnect the control unit connector.
3. Using a voltmeter, measure voltage between ground and terminals 49 (W), 50 (W), 51 (WR), 52 (WR), 53 (WY) and 54 (WY) on the control unit connector.
4. The voltmeter should read 12 volts at all terminals.
5. If the voltmeter reads below 10 volts in any line, the harness from the battery to the control unit through the resistor and injector is broken or shorted.
6. Disconnect each fuel injector electrical connector.
7. Using an ohmmeter, measure resistance between the terminals of each injector. The ohmmeter should read 13.8 ohms at each injector. If the ohmmeter reads infinity, the circuit is broken. If the ohmmeter reads 0 ohm, the circuit is shorted. Replace injector.
8. Using a voltmeter, measure voltage between the terminals of each injector and ground. The voltmeter should read 12 volts at each injector. If the voltage obtained is less than 10 volts at any injector, the harness from the battery to the injector is disconnected or shorted.

3.3L Engine

1. Using a stethoscope, ensure that a clicking sound is heard at each injector (when idling or cranking the engine).
2. Turn the ignition switch OFF. Disconnect the fuel injector connector.
3. Measure the voltage between fuel injector connector terminal 2 and ground. Voltage should be 10 volts minimum. If not, repair the harness or connector.
4. Measure the resistance between the injector terminals. Resistance should be 11–12 ohms. If not, replace the fuel injector.
5. Fasten the fuel injector connector.
6. Measure the voltage between each fuel injector terminal of the ECU connector and ground. Resistance should be as follows:
   • Terminal 1 and ground: 10 volts minimum
   • Terminal 11 and ground: 10 volts minimum
   • Terminal 12 and ground: 10 volts minimum
   • Terminal 13 and ground: 10 volts minimum
   • Terminal 26 and ground: 10 volts minimum
   • Terminal 12 (connector E59) and ground: 10 volts minimum
7. If not within specification, repair the harness or connector.
8. Disconnect the ECU harness.
9. Measure the resistance between ground and ECU connector terminals 24 and 25. Resistance should be 0 ohms, if not, repair the harness or connector.