CHAIN AS 2072668 - Caterpillar

Power Train Electronic Control Module (ECM)
Illustration 1 g00375318
Right Side of the Machine (1) Power Train Electronic Control Module (ECM).The power train ECM is located on the right side of the machine under the right side platform. The primary function of the power train ECM is shifting the transmission. In order for the transmission to be shifted to the desired speed and to the desired direction, the power train ECM receives the operator input from the STIC steering and transmission control.The power train ECM also controls starting the engine and the backup alarm. The power train ECM will not allow the engine to be started unless the direction control switch is in the NEUTRAL position. The backup alarm is activated whenever the direction control switch is in the REVERSE position.The power train ECM controls the torque converter impeller clutch and the torque converter lockup clutch.The power train ECM has built-in system diagnostics in order to detect faults in the power train electrical system. The power train ECM has a diagnostic display. The diagnostic display consists of three LED lights and a three digit display.For more information on the operation of the power train ECM and troubleshooting the power train ECM, refer to Service Manual, SENR5704, "Electronic Transmission Control System".STIC Steering and Transmission Control
Illustration 2 g00107001
STIC Steering and Transmission Control (2) Transmission downshift switch. (3) Transmission upshift switch. (4) STIC transmission direction control switch. (5) Steering and transmission lock control.The STIC steering and transmission control is a sealed unit. The STIC steering and transmission control is positioned on the left console. STIC transmission direction control switch (4) is a three-position switch that selects either neutral, forward, or reverse. Transmission upshift switch (3) makes momentary contact in order to select the next higher speed. Transmission downshift switch (2) makes momentary contact in order to select the next lower speed.STIC Steering and Transmission Lock Control
When the STIC steering and transmission lock control (5) is moved to the LOCKED position, steering is disabled and a switch is depressed. The closed switch causes the power train ECM to shift the transmission into neutral.When the STIC steering and transmission lock control is moved to the UNLOCK position, the operator has control of the steering and control of the transmission. The power train ECM will not shift the transmission into a speed until the direction control switch is first moved into the NEUTRAL position.Parking Brake Interlock
When the parking brake control is disengaged, the transmission will shift normally. When the parking brake control is engaged, the transmission will not shift out of neutral to first speed forward or first speed reverse. If the transmission is in first speed forward or in first speed reverse and the parking brake is moved to the engaged position, the transmission will shift into neutral. If the transmission is in second speed forward or in third speed forward, the transmission will remain engaged.When the power train ECM shifts the transmission to neutral, the power train ECM will not shift the transmission into a speed