Transfer Case Shift Control Switch Inoperative or 4 Low Indicator Stuck on

Transfer Case Shift Control Switch Inoperative or 4 Low Indicator Stuck on

Circuit Description

The transfer case shift control switch circuit consists of three normally open switches. From the 4WD fuse the switch is supplied with ignition 3 voltage. When one of the switches is pressed, current travels through the switch to its corresponding signal circuit and to the transfer case shift control module. The transfer case shift control module continuously monitors the switch inputs to determine whether the 2HI, 4HI, or 4LO buttons have been selected by the driver.

Test Description

The numbers below refer to the step numbers on the diagnostic table.

2. This step tests the functionality of the transfer case shift control switch buttons.
3. This step tests the transfer case shift control switch for proper function.
4. This step tests the individual switch signal circuits.
5. This step tests the transfer case shift control switch ignition 3 circuit for proper voltage.
6. This step tests the transfer case shift control switch for proper function.
8. This step determines if the vehicle is equipped with an automatic or manual transmission.
9. This step tests the A/T shift lock switch supply voltage circuit for proper voltage.
10. This step repairs an open or high resistance in the A/T shift lock switch supply voltage circuit.
11. This step tests the suspect switch signal circuit for an open or high resistance.
12. This step tests the 4WD fuse for an open.
13. This step repairs an open in the transfer case shift control switch ignition 3 voltage circuit.
14. This step tests the 4WD fuse to determine if it re-blows.
15. The step tests the transfer case shift control switch ignition 3 voltage circuit and the transfer case shift control switch signal circuits for a short to ground.

Transfer Case Shift Control Switch Inoperative