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COMPONENT INSPECTION

2.4L Engines

NOTE: The 1993–95, rear-wheel drive 2.4L (California) Pick-ups have the same engine controls as the 3.0L engines. All other 2.4L engines are listed as 2.4L engines.

  1. Remove the MFI relay.
  2. Check the continuity between the MFI relay terminals. Check terminals 3–5 and 2–5, which should register approximately 95 ohms. Check terminals 6–7, which should register 35 ohms. Check terminals 6–8, which will only be connected one way.
  3. By using the jumper wire, connect terminal 7 of the MFI relay to the (+) terminal of the battery and terminal 6 to the (-) terminal of the battery.

    WARNING
    If the jumper leads are not connected to the proper terminals, the relay will be damaged.

  4. While connecting the jumper wire on the (-) side of the battery, check continuity between the terminals 1 and 4 of the MFI relay. While connected, the resistance should be 0 ohms, and infinite resistance when disconnected.

    Fig. 1: Testing connections for the MFI relay — if the relay does not pass all of the tests, it needs to be replaced with a new unit

  5. By using the jumper wire, connect terminal 2 of the MFI relay to the (+) terminal of the battery and terminal 5 to the (-) terminal of the battery.
  6. While connecting the jumper wire on the (-) side of the battery, check continuity between the terminals 1 and 4 of the MFI relay. While connected, the resistance should be 0 ohms, and infinite resistance when disconnected.
  7. By using the jumper wire, connect terminal 8 of the MFI relay to the (+) terminal of the battery and terminal 6 to the (-) terminal of the battery.
  8. While connecting the jumper wire on the (-) side of the battery, check continuity between the terminals 2 and 4 of the MFI relay. While connected, the resistance should be 0 ohms, and infinite resistance when disconnected.
  9. Replace the MFI relay with a new one, if a malfunction occurred with the tests.
3.0L (12 Valve) Engines
  1. Remove the MFI relay.
  2. By using the jumper wire, connect terminal 10 of the MFI relay to the (+) terminal of the battery and terminal 8 to the (-) terminal of the battery.

    WARNING
    If the jumper leads are not connected to the proper terminals, the relay will be damaged.

    Fig. 2: Testing connections for the MFI relay — if the relay does not pass all of the tests, it needs to be replaced with a new unit

  3. While connecting the jumper wire on the (-) side of the battery, check the voltage at terminals 4 and 5 of the MFI relay. While connected the voltage should be the battery voltage, and the voltage should be 0 volts when disconnected.
  4. By using the jumper wire, connect terminal 9 of the MFI relay to the (+) terminal of the battery and terminal 6 to the (-) terminal of the battery.
  5. While connecting the jumper wire on the (-) side of the battery, check continuity between the terminals 2 and 3 of the MFI relay. While connected the continuity should be 0 ohms, and the continuity should be ∞ ohms when disconnected.
  6. By using the jumper wire, connect terminal 3 of the MFI relay to the (+) terminal of the battery and terminal 7 to the (-) terminal of the battery.
  7. While connecting the jumper wire on the (-) side of the battery, check the voltage between at terminal 2 of the MFI relay. While connected the voltage should be the battery voltage, and the voltage should be 0 volts when disconnected.
  8. Replace the MFI relay with a new one, if a malfunction occurred with the tests.
3.0L (24 Valve) and 3.5L Engines
  1. Remove the MFI relay.
  2. Check the continuity between the MFI relay terminals. Check terminals 5–7, which should register continuity. Check terminals 6–8, which will only show continuity in one direction.

    Fig. 3: The numbered terminals on the MFI relay — 3.0L (24 valve) and 3.5L engines

  3. By using the jumper wire, connect terminal 7 of the MFI relay to the (+) terminal of the battery and terminal 5 to the (-) terminal of the battery.

    WARNING
    If the jumper leads are not connected to the proper terminals, the relay will be damaged.

    Fig. 4: Relay test connections — 3.0L (24 valve) and 3.5L equipped vehicles

    Fig. 5: Relay test connections — 3.0L (24 valve) and 3.5L equipped vehicles

  4. While connecting the jumper wire on the (-) side of the battery, check the voltage at terminal 1 of the MFI relay. While connected the voltage should be the battery voltage, and the voltage should be 0 volts when disconnected.
  5. By using the jumper wire, connect terminal 8 of the MFI relay to the (+) terminal of the battery and terminal 6 to the (-) terminal of the battery.
  6. While connecting the jumper wire on the (-) side of the battery, check continuity between the terminals 1–4 and 3–4 of the MFI relay. While connected the continuity should be 0 ohms, and the continuity should be ∞ ohms when disconnected.
  7. Replace the MFI relay with a new one, if a malfunction occurred with the tests.

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