Circuit/System Testing

Ignition/Vehicle - Off
Disconnect the electrical connector: A16 Transfer Case Four Wheel Drive Actuator
Connect a test lamp between the test points: Control circuit terminal A & Control circuit terminal D
Start the vehicle and place the transmission in Neutral.
Perform the scan tool control function:Range Actuator
Verify the test lamp state:

Range Actuator - Idle = Test lamp Off

Range Actuator - Clockwise = Test lamp On

Range Actuator - Counterclockwise = Test lamp On
- If not the specified state
1. Ignition/Vehicle - Off & Remove - Test lamp
2. Disconnect the electrical connector:X1@K69 Transfer Case Control Module
3. Use jumper wires to connect the CAN Bus serial data circuits together at the K69 Transfer Case Control Module connector. Jumper circuit 4979 to 4979. Jumper circuit 4978 to 4978.
4. Ignition - On/Vehicle - In Service Mode
5. Test for less than 1 V between the test points:
  - Control circuit terminal A@Component harness & Ground
  - Control circuit terminal D@Component harness & Ground
  - If 1 V or greater - Repair the short to voltage on the circuit.
  - Go to next step: If less than 1 V
6. Ignition/Vehicle - Off
7. Test for infinite resistance between the test points:
  - Control circuit terminal A@Component harness & Ground
  - Control circuit terminal D@Component harness & Ground
  - If less than infinite resistance - Repair the short to ground on the circuit.
  - Go to next step: If infinite resistance
8. Test for less than 2 ohms between the test points:
  - Control circuit terminal A@Component harness & Terminal 38@Control module harness
  - Control circuit terminal D@Component harness & Terminal 13@Control module harness
  - If 2 ohms or greater - Repair the open/high resistance in the circuit.
  - If less than 2 ohms - Replace the component:K69 Transfer Case Control Module
- Go to next step: If the specified state
Test or replace the component:A16 Transfer Case Four Wheel Drive Actuator