Pinpoint Test D: The Transmission Control (TC) Switch Does Not Operate Correctly

D1 CHECK FUSE F8 (10A)
- Check fuse: CJB Fuse F8 (10A).
- Is the resistance less than 5 ohms?
Yes : GO to D3.

No : GO to D2.
D2 CHECK CIRCUIT 640 (RD/YE) FOR A SHORT TO GROUND
- Key in OFF position.
- Disconnect: CJB Fuse F8 (10A).
- Measure the resistance between the output side of fuse F8 (10A) and ground.
  
  Fig 1: Checking Circuit 640 (RD/YE) For Short To Ground
- Is the resistances greater than 10,000 ohms?
Yes : GO to D4.

No : REPAIR circuit 640 (RD/YE). REINSTALL all components. TEST the system for normal operation.
D3 CHECK CIRCUIT 640 (RD/YE) FOR AN OPEN
- Key in OFF position.
- Disconnect: CJB Fuse F8 (10A).
- Disconnect: Transmission Control (TC) Switch C279.
- Measure the resistance between the output side of fuse F8 (10A) and TC switch C279-1.
  
  Fig 2: Checking Circuit 640 (RD/YE) For Open
- Is the resistance less than 5 ohms?
Yes : GO to D5.

No : REPAIR circuit 640 (RD/YE). RECONNECT all components. TEST the system for normal operation.
D4 CHECK SELECTOR LEVER HARNESS FOR A SHORT TO GROUND
- Key in OFF position.
- Disconnect: Transmission Control (TC) Switch C279.
- Measure the resistance between TC switch C279-1 and ground while cycling the TC switch.
  
  Fig 3: Checking Selector Lever Harness For Short To Ground
- Is the resistance greater than 10,000 ohms?
Yes : GO to D6.

No : INSTALL a new selector lever. REFER to SELECTOR LEVER in this article. RECONNECT all components. TEST the system for normal operation.
D5 CHECK THE TRANSMISSION CONTROL (TC) SWITCH
- Key in OFF position.
- Measure the resistance between TC switch C279-1 and C279-2 while cycling the TC switch.
  
  Fig 4: Checking Transmission Control Switch
- Does the resistance change from less than 5 ohms to greater than 10,000 ohms?
Yes : GO to D7.

No : INSTALL a new TC switch. REFER to SELECTOR LEVER in this article. REINSTALL all components. TEST the system for normal operation.
D6 CHECK CIRCUIT 224 (TN/WH) FOR A SHORT TO GROUND
- Disconnect: Powertrain Control Module (PCM) C175b.
- Measure the resistance between transmission control (TC) switch C279-2 and ground.
  
  Fig 5: Checking Circuit 224 (TN/WH) For Short To Ground
- Is the resistance greater than 10,000 ohms?
Yes : INSTALL a new PCM. RECONNECT all components. TEST the system for normal operation.

No : REPAIR circuit 224 (TN/WH). RECONNECT all components. TEST the system for normal operation.
D7 CHECK CIRCUIT 224 (TN/WH) FOR AN OPEN
- Disconnect: Powertrain Control Module (PCM) C175b.
- Measure the resistance between transmission control (TC) C279-2 and PCM C175b-27.
  
  Fig 6: Checking Circuit 224 (TN/WH) For Open
- Is the resistance less than 5 ohms?
Yes : INSTALL a new PCM. RECONNECT all components. TEST the system for normal operation.

No : REPAIR circuit 224 (TN/WH). RECONNECT all components. TEST the system for normal operation.