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Code 63: Blower Fan Switch

NOTE: Refer to illustration for ECU connector and terminal identification. See Figure .
  1. Disconnect ECU connectors. Turn ignition on. Measure voltage between ground and ECU connector F120, terminal No. 11 (Green/White wire). With blower motor off, voltage should be more than 8 volts. With blower motor on high, voltage should be less than 2 volts. If voltage is as specified, go to next step. If voltage is not as specified, repair faulty heater fan switch or wiring harness connector.
  2. Turn ignition off. Measure resistance between ground and ECU connector F119, terminal No. 1 (Brown wire). Measure resistance between ground and ECU connector F120, terminal No. 10 (Brown wire). If both resistances are less than 10 ohms, check for poor ECU connector contact. Repair connector and/or wiring harness as necessary. If connector and wiring harness are okay, replace ECU. If either resistance is more than 10 ohms, repair connector and/or wiring harness as necessary.