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No Codes - Functional Test Not Operating

  1. Ensure that test connections, jumper wires, and VOM were all correctly hooked up.
  2. Disconnect MCU connector. With ignition on, battery voltage should be present at pin 20. If not, check fuse. With ignition off, pin 14 should have continuity to ground. If not, repair. If wiring is okay, go to next step.
  3. Check for continuity between Self-Test connector and MCU. See wiring diagram at end of this test for wire connections. Check to ensure circuit from MCU to TAD solenoid is not shorted to ground.
  4. Measure TAB solenoid resistance. If within 50-110 ohms, replace MCU module. If not within 50-110 ohms, replace solenoid. Repeat "Functional Test".
Fig 1: Diagnostic Circuit Wiring Diagram
G195