3C8743 MAST AS. Caterpillar parts
Alternative (cross code) number:
Weight: 0.02 pounds 0 kg.
Illustration 4 g01207582
Terminal locations at the P1 ECM connector
(P1-5) Digital return
(P1-66) Throttle signal
Illustration 5 g01207583
Terminal locations at the engine interface connector
(15) Digital return
(21) Throttle signal
Perform a 45 N (10 lb) pull test on each of the wires in the ECM connector and the engine interface connector that are associated with the circuit.
Check the allen head screw on each ECM connector and the engine interface connector for the proper torque. refer to the diagnostic functional test Troubleshooting, "Electrical Connectors - Inspect" for the correct torque values.
Check the harness and the wiring for abrasion and for pinch points. Expected Result:All connectors, pins, and sockets are completely coupled and/or inserted, and the harness and wiring are free of corrosion, of abrasion or of pinch points.Results:
OK - The connectors and wiring appear to be OK. Proceed to Test Step 2.
Not OK - The connectors and/or wiring are not OK.Repair: Repair the connectors or wiring and/or replace the connectors or wiring.Repair CompleteTest Step 2. Check the Supply Voltage to the Speed Control
Restore electrical power to the ECM.
Measure the voltage between terminal 15 (+Battery) and terminal 16 (−Battery) on the speed control.