PLATE 2166359 - Caterpillar

Illustration 1 g00776399
Schematic for the Transmission Auto/Manual SwitchThis diagnostic code is recorded when the status of all four switch inputs of the power train ECM are open.The transmission auto/manual switch has five inputs to the power train electronic control module (ECM). During normal operation, one input is grounded while the other inputs are open. The valid combinations for each switch position are shown in table 1 that follows. If an invalid combination is detected by the power train ECM, a circuit failure is present.
Table 1
Auto/Manual Switch Status    
Switch
Position     Man
J1-29     Auto 4
J1-31     Auto 3
J1-33     Auto 2
J1-32     Auto
1-4
J2-10    
Auto 1-4     O (1)     O     O     O     G (2)    
Auto 2-2     O     O     O     G     O    
Auto 2-3     O     O     G     O     O    
Auto 2-4     O     G     O     O     O    
Manual     G     O     O     O     O    
( 1 ) O means Open.
( 2 ) G means Grounded.Possible causes of this diagnostic code are listed:
Failed harness
Failed switchSystem Response:The machine response is listed:
The autoshift is disabled.Note: The following procedure can create other diagnostic codes that can be detected by the power train ECM. Ignore these created diagnostic codes and clear the created diagnostic codes when this diagnostic code is corrected.Note: Ensure that the diagnostic code is active and that the diagnostic code indicator is active.Test Step 1. Check the Ground Circuit.
Turn the disconnect switch to the OFF position.
At the screw terminals of the switch, measure the resistance between wire 202-BK and frame ground.Expected Result:The resistance should be 2 Ohms or less.Results:
YES - The resistance is 2 Ohms or less. Proceed to test step 2.
NO - The resistance is greater than 2 Ohms.Repair: Wire 202-BK is open in the harness between the switch and frame ground. Repair the harness or replace the harness. Stop.Test Step 2. Check the Switch.
Turn the disconnect switch and the key start switch to the ON position.
Ensure that the diagnostic code is active and that the diagnostic code indicator is active.
Disconnect the switch from the harness. Observe the ON/OFF status of the diagnostic code indicator.
At the harness connector for the switch, jumper the N/C contact to ground.Reference: Refer to Table 1 for the appropriate connector contacts.Expected Result:The diagnostic code indicator should remain active.Results:
YES - The diagnostic code indicator remains active. Proceed to test step 3.
NO - The diagnostic code indicator does not remain active.Repair: Repeat the previous test step in order to verify that the switch has failed. Replace the switch. Repair the harness or replace the harness. Stop.Test Step 3. Check the Circuit.This step checks the continuity of the entire harness circuit that is related to this diagnostic code. The switch that was checked in the previous step is also checked in this step.
Turn the disconnect switch to OFF position.
Remove the jumper that was installed in the previous test