Pinpoint Test C: The Transmission Control (TC) Switch Is Inoperative

2009 Ford Edge Sport, FWDSECTION Pinpoint Test C: The Transmission Control (TC) Switch Is Inoperative
WARNING: This page is about a different car, the 2009 Ford Mustang. However, it is still accessible from the selected car via links, so may be relevant.
  1. C1 CHECK THE VOLTAGE TO THE TRANSMISSION CONTROL (TC) SWITCH 
    • Key in OFF position.
    • Disconnect: Selector Lever C307
    • Key in ON position.
    • Fig 1: Measuring Voltage Between Selector Lever C307-5, Circuit 1862 (VT/WH), Harness Side & Ground
      GF0000988Courtesy of FORD MOTOR CO.
    • Measure the voltage between selector lever C307-5, circuit 1862 (VT/WH), harness side, and ground.
    • Is the voltage greater than 10 volts? 
    1. YES  : Go to  C2.
    2. NO  : REPAIR the circuit. TEST the system for normal operation.
  2. C2 CHECK THE TC SWITCH 
      Fig 2: Measuring Resistance Between Selector Lever C307-5 & C307-6, Component Side
      GF0000989Courtesy of FORD MOTOR CO.
    • Measure the resistance between selector lever C307-5 and C307-6, component side, while depressing and releasing the TC switch.
    • Is the resistance less than 5 ohms with the TC switch depressed and greater than 10,000 ohms with the TC switch released? 
    1. YES  : Go to  C3.
    2. NO  : INSTALL a new selector lever knob. TEST the system for normal operation.
  3. C3 CHECK CIRCUIT 224 (TN/WH) FOR AN OPEN 
    • Key in OFF position.
    • Disconnect: PCM C175B
    • Fig 3: Checking Circuit 224 (TN/WH) For An Open
      GF0046431Courtesy of FORD MOTOR CO.
    • Measure the resistance between selector lever C307-6, circuit 224 (TN/WH), harness side and PCM C175B-29, circuit 224 (TN/WH), harness side.
    • Is the resistance less than 5 ohms? 
    1. YES  : Go to  C4.
    2. NO  : REPAIR the circuit. TEST the system for normal operation.
  4. C4 CHECK CIRCUIT 224 (TN/WH) FOR A SHORT TO GROUND 
      Fig 4: Checking Circuit 224 (TN/WH) For A Short To Ground
      GF0046432Courtesy of FORD MOTOR CO.
    • Measure the resistance between selector lever C307-6, circuit 224 (TN/WH), harness side and ground.
    • Is the resistance greater than 10,000 ohms? 
    1. YES  : INSTALL a new PCM. REFER to ELECTRONIC ENGINE CONTROLS article. TEST the system for normal operation.
    2. NO  : REPAIR the circuit. TEST the system for normal operation.
RENDER: 1.0x

NO RELATED

Recommended Tools & Savings

Use the Manual With the Right Hardware

Pair factory procedures with proven DIY tools so the instructions are easier to execute.

Affiliate disclosure: We may earn a commission at no extra cost to you.

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • You smell fuel, burning insulation, or see smoke.
  • Brakes feel soft, pull hard to one side, or make grinding noises.
  • The engine overheats, stalls repeatedly, or misfires under load.
  • You are missing required tools, torque specs, or safe lifting equipment.
  • You are not confident in the next step or safety outcome.