BOLT 7X0825 - Caterpillar

System Operation Description:Use this procedure in order to troubleshoot suspect problems with the circuit for the throttle actuator.This procedure covers the following diagnostic codes:
1440-9 Throttle Actuator : Abnormal Update Rate
1440-11 Throttle Actuator invalid
1440-12 Throttle Actuator : FailureThe throttle actuator is an electronic actuator that works with the Electronic Control Module (ECM) in order to ensure the correct throttle position in all conditions of engine operation.The ECM and the throttle actuator communicate via the CAN data link. The ECM sends a command signal to the actuator. The actuator sends the following information to the ECM: actuator position, CCM heartbeat, software version and internal fault diagnosis.If the ECM cannot communicate with the throttle actuator, the ECM activates a 1440-9 diagnostic code and the engine is shut down. A 1440-9 diagnostic code is probably caused by a problem with an electrical connector or a harness. The next likely cause is a problem with the actuator. The least likely cause is a problem with the ECM.Terminating resistors must be connected to each end of the CAN data link. The terminating resistors improve the communication between the devices. If there is an intermittent diagnostic code for any of the devices that are connected to the CAN data link, be sure to check the terminating resistor that is on the right side of the terminal box. Also check the terminating resistor that is on the right front side of the engine. The resistor will be near the compressor bypass valve. Replace parts, if necessary.Logged diagnostic codes provide a historical record. Before you begin this procedure, use Caterpillar Electronic Technician (ET) to print the logged codes to a file.This troubleshooting procedure may generate additional diagnostic codes. Keep your mind on correcting the cause of the original diagnostic code. Clear the diagnostic codes after the problem is resolved.
Illustration 1 g02291301
Schematic for the circuit of the throttle actuator
Test Step 1. Inspect the Electrical Connectors and Wiring
Remove the electrical power from the engine. Note: For the following steps, refer to Troubleshooting, "Electrical Connectors - Inspect".
Thoroughly inspect each of the following connectors:
J1/P1 connectors
J9/P9 connectors
Connectors on the throttle actuator
Check the torque of the allen head screw for the ECM connectors.
Perform a 45 N (10 lb) pull test on each of the wires that are associated with the throttle actuator.
Illustration 2 g01065718
Right side view with the throttle actuator
Check the wiring for abrasion and for pinch points from the throttle actuator to the ECM. Expected Result:All of the connectors, pins, and sockets are connected properly. The connectors and the wiring do not have corrosion, abrasion, or pinch points.Results:
OK - The components are in good condition with proper connections. Proceed to Test Step 2.
Not OK - The components are not in good condition and/or at least one connection is improper.Repair: Perform the necessary repairs and/or replace parts, if necessary. Ensure that all of the seals are properly installed. Ensure that the connectors are properly engaged. Verify that the repair has eliminated the original problem.STOPTest Step 2. Check for Diagnostic Codes
Connect Cat ET to the service