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Code 45 - Pressure Sensor, Pressure Exchange Solenoid ALVE (Turbo)

  1. Check connection between pressure sensor and rubber hose, between pressure exchange solenoid valve and rubber hose, and between intake manifold and rubber hose. Disconnect pressure sensor connector. Apply 5 volts to pressure sensor connector terminals No. 1 (White wire) and ground to terminal No. 2 (Red wire).
  2. Install vacuum pump to hose fitting on pressure sensor. Measure voltage between terminals No. 2 (Red wire) and No. 3 (Black wire) while applying vacuum to pressure sensor. See the PRESSURE SENSOR VOLTAGE  table. If voltages are to specification, go to next step. If voltages are not to specification, replace pressure sensor.
    PRESSURE SENSOR VOLTAGE

    Vacuum Volts
    7.87 in. Hg 3.1
    0 in. Hg 2.6
    -7.87 in. Hg 2.1
  3. Disconnect pressure exchange solenoid valve connector. Measure resistance between connector terminals No. 1 (Green/Yellow wire) and No. 2 (Yellow/Red wire). If resistance is 37-48 ohms, go to next step. If resistance is not 37-48 ohms, replace pressure exchange solenoid valve.
  4. Reconnect connector and rubber hose to pressure sensor. Reconnect connectors to pressure exchange solenoid valve. Turn ignition on. Measure voltage between ECU connector terminal and ground. See ECU VOLTAGE SPECIFICATIONS table. If voltages are to specification, repair ECU terminals for poor contact. If terminals are okay, replace ECU. If voltages are not to specification, go to next step.
    ECU VOLTAGE SPECIFICATIONS

    ECU Terminal Volts
    No. 3 (1) 5
    No. 4 (1) 2.4-2.7
    No. 5 (1) Zero
    No. 20 (2) Zero or 10-13
    (1) Measure at ECU connector B48.
    (2) Measure at ECU connector F47.
  5. Disconnect ECU and pressure sensor connectors. Measure resistance between ECU connector B48, terminal No. 3 and pressure sensor terminal No. 1 (White wire), between ECU connector B48, terminal No. 4 and pressure sensor terminal No. 3 (Black wire), and between ECU connector B48, terminal No. 5 and pressure sensor terminal No. 2 (Red wire). If all measurements are zero ohms, go to next step. If any measurement is not zero ohms, repair harness as necessary.
  6. Measure resistance between ground and ECU connector B48, terminals No. 3, 4 and 5. At least one megohm should be present. If resistance is not at least one megohm, repair harness as necessary. If resistance is to specification, go to next step.
  7. Disconnect ECU and pressure exchange solenoid valve connectors. Measure resistance between ECU connector F47, terminal No. 20 and pressure exchange solenoid valve connector terminal No. 1 (White wire). Zero ohms should be present. Measure resistance between ECU connector F47, terminal No. 20 and ground. At least one megohm should be present. If resistances are not to specification, repair harness or connector as necessary. If resistances are to specification, go to next step.
  8. Disconnect pressure exchange solenoid valve and ignition relay connector. Measure resistance between pressure exchange solenoid valve connector terminal No. 2 (Yellow/Red wire) and ignition relay connector terminal No. 4 (Yellow/Red wire). If resistance is zero ohms, check ECU terminals for poor contact. If terminal contact is okay, replace ECU. If resistance is not to specification, repair harness or connector as necessary.
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