CLUTCH ASSEMBLY 06000030 - Caterpillar

Key Start Switch
Illustration 10 g00291705
Key Start SwitchThe key start switch is an input of the ECM. The switch connects to connector contact J1-40. The switch tells the ECM that the operator wants to start the engine. The ECM then initiates the neutral start function. See Systems Operation, "Neutral Start Function" for more information. The signal is open during normal operation. When the key start switch is in the START position, the switch will close to the +battery circuit.The switch has four terminals. Terminal "S" connects to the ECM. Terminal "B" connects to battery voltage. Terminal "C" connects to the engine shutdown control. Terminal "R" connects to the main relay.Note: After the switch is initially turned to the START position, the switch will not return to the START position from the ON position. The switch must be turned to the OFF position. The switch can then be turned to the START position.The ECM does not record diagnostic codes that occur with the key start switch. Retarder Lever
(S/N: AGFAFX)
Illustration 11 g00805529
Schematic of the Retarder Lever
Table 1
Circuit Continuity    
Retarder Lever Switch    
Lever Position     Connector Contact (2) of the Switch     Connector Contact (3) of the Switch     Connector Contact (4) of the Switch    
1     Off     Open (1)     Open     Open    
2     Low     Open     Open     Closed (2)    
3     Med     Closed     Open     Closed    
4     High     Open     Closed     Closed    
( 1 ) Open Circuit
( 2 ) Circuit ContinuityThe retarder lever is an input to the ECM. The retarder lever connects to the ECM through connector contacts J1-55, J1-56, and J1-57. The retarder lever connects to ground at J1-12. The retarder lever tells the ECM the desired setting for the retarder. The retarder has four positions. The OFF position, the LOW position, the MEDIUM position and the HIGH position. Table 1 shows the state of the contacts in each of the positions. See Systems Operation, "Retarder Function" for additional information on the function of the retarder lever.Switch (Top Drive Gear)
The switch is an input to the ECM. The switch connects to the ECM through connector contact J1-47. Ground is at J1-12. The switch limits the highest gear that is engaged by the transmission. The ECM then restricts the transmission from shifting past the indicated top gear. The switch is located on the shift lever. The switch is located under the operator's thumb.The gear positions for the gear selector are listed:
First
Second
Third
Drive
Neutral
ReverseThe drive position on the gear selector is used in order to select the gears from the fourth gear to the top gear.When the gear selector is in the drive position, the operator uses the top drive gear switch in order to select the desired setting of the gear selector. Before the drive gear decreases, the top drive gear is activated for 5.0 seconds.The drive gear is held to the current value for 2.5 seconds before the drive gear will decrease