Pinpoint Test E: Park Neutral Signal

WARNING: This page is about a different car, the 2006 Mercury Milan, 2006 Lincoln Zephyr, and 2006 Ford Fusion. However, it is still accessible from the selected car via links, so may be relevant.

E1 CHECK FOR VOLTAGE ON CIRCUIT 199
- Disconnect: Transmission Control Module (TCM) Connector C168.
- Key in ON position.
- Range selector lever in PARK or NEUTRAL.
- Measure the voltage on C168-5 and chassis ground.
  
  Fig 1: Checking For Voltage On Circuit 199
  Courtesy of FORD MOTOR CO.
- Is the voltage between 0-0.8 volt?
Yes : GO to E2.

No : GO to E3.
E2 CHECK FOR VOLTAGE ON CIRCUIT 199
- Disconnect: TCM Connector C168.
- Key in ON position.
- Range selector lever in REVERSE, DRIVE or LOW.
- Measure the voltage on C168-5 and chassis ground.
  
  Fig 2: Checking For Voltage On Circuit 199
  Courtesy of FORD MOTOR CO.
- Is the voltage greater than 10 volts?
Yes : INSTALL a new TCM. After installing the new TCM, VERIFY that the starting system is operating correctly. If not, GO to ENGINE COOLING to check starting system.

No : GO to E3.
E3 CHECK VEHICLE HARNESS CIRCUIT 199 FOR A SHORT
- Disconnect: PCM Connector C175T.
- Disconnect: Transmission Module C168.
- Measure the resistance between C168-5 and C175T-19.
  
  Fig 3: Checking Vehicle Harness Circuit 199 For Short
  Courtesy of FORD MOTOR CO.
- Is the resistance greater than 10,000 ohms?
Yes : GO to E4.

No : REPAIR short in circuit 199.
E4 CHECK VEHICLE HARNESS CIRCUIT 199 FOR AN OPEN
- Disconnect: PCM Connector C175T.
- Disconnect: Transmission Module C168.
- Measure the resistance between C168-5 and chassis ground.
  
  Fig 4: Checking Vehicle Harness Circuit 199 For Open
  Courtesy of FORD MOTOR CO.
- Is the resistance greater than 10,000 ohms?
Yes : REPAIR the open in circuit 199.

No : INSTALL a new TCM. After installing the new TCM, VERIFY that the starting system is operating correctly. If not, GO to ENGINE COOLING to check starting system.