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Code 24 - By-Pass Air Control Solenoid Valve

NOTE: Refer to illustration for ECU connector and terminal identification. See Figure .
  1. Turn ignition on. Measure voltage between by-pass air control valve connector terminal No. 2 (Yellow/Red wire) and ground. If 10 volts are present, go to next step. If 10 volts are not present, repair circuit between by-pass air control solenoid valve and battery.
  2. Disconnect by-pass air control solenoid valve connector. Measure resistance between by-pass air control solenoid valve connector terminals No. 1 (White wire) and No. 2 (Yellow/Red wire), and between terminals No. 2 (Yellow/Red wire) and No. 3 (Black wire). If 9 ohms are present in all measurements, go to next step. If 9 ohms are not present in all measurements, replace solenoid valve.
  3. Turn ignition on. Measure voltage between ECU connector F47, terminal No. 1 (backprobe) and ground, and No. 2 and ground. See the ECU TERMINAL SPECIFIED VOLTAGE  table. If voltage is to specification, repair poor contact at ECU terminal or replace ECU. If voltage is not to specification, go to next step.
    ECU TERMINAL SPECIFIED VOLTAGE

    Connector & Terminal Voltage
    Non-Turbo
    No. 2 (1) & Ground 7
    No. 1 (1) & Ground 6
    Turbo
    No. 2 (1) & Ground (2) 0-12
    No. 1 (1) & Ground (2) 12-0
    (1) Measure at ECU connector F47.
    (2) Specification is a voltage switch one minute after ignition is turned on.
  4. Turn ignition off. Disconnect ECU and by-pass air control solenoid valve connectors. Measure resistance between ECU connector F47, terminal No. 2 and by-pass air control solenoid valve connector terminal No. 1 (White wire). Measure resistance between ECU connector F47, terminal No. 1 and by-pass air control solenoid valve connector No. 3. Zero ohms should be present in both cases. If zero ohms is present in all cases, go to next step. If zero ohms is not present in all cases, repair harness as necessary.
  5. Measure resistance between ground and solenoid valve terminals No. 1 (White wire) and No. 3 (Black wire). At least one megohm should be present in both cases. If resistance is not at least one megohm in both cases, replace solenoid valve. If one megohm is present in both cases, check for poor ECU terminal contact or replace ECU.
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