KIT-SEAL 2896338 - Caterpillar

Table 2
Status of the Transmission Upshift Switch
Command Control Steering    
Switch Position     N/C
J1-19     N/O
J1-23    
Depressed     Open     Closed    
Released     Closed     Open    Note: The normally closed (N/C) circuit and normally open (N/O) circuit of the transmission upshift switch is used for diagnostic purposes. If the normally closed (N/C) circuit and the normally open (N/O) circuit are open at the same time, the power train ECM records a fault. If the normally closed (N/C) circuit and the normally open (N/O) circuit are grounded at the same time, the power train ECM records a fault.Switch (Transmission Downshift)
Illustration 5 g00813690
(1) Transmission upshift switch (2) Transmission downshift switch (3) Transmission direction control switchTransmission downshift switch (2) makes momentary contact in order to select the next lower speed. The operator selects a speed by depressing transmission upshift switch (1) or by depressing transmission downshift switch (2). Transmission downshift switch (2) has two input connections to the power train electronic control module (ECM) on connector J1: downshift N/C at contact 25 and downshift N/O at contact 26. When the operator presses the downshift switch, the downshift N/C circuit is open and the downshift N/O circuit is closed to ground. When the switch is not activated, the downshift N/C circuit is closed to ground and the downshift N/O circuit is open. The valid combinations for each switch position are shown in Table 3 that follows.ReferenceFor more information on the function of the transmission downshift switch, refer to Systems Operation, "Power Train Electronic Control System" for the