KIT-ENGINE OVERHAUL 4549089 - Caterpillar

Illustration 1 g03426166
Schematic of the Engine Speed Dial switch
This diagnostic code is recorded when the ECM cannot communicate with the Engine Speed Dial switch.Possible causes of this diagnostic code are:
The switch has failed.
The machine harness has failed.
The Machine ECM may have failed, but this situation is unlikely.Test Step 1. CHECK THE SWITCH.
Turn the disconnect switch and the key start switch to the OFF position.
Disconnect the Engine Speed Dial switch from the machine harness.
Use Table 1 to check resistance on the rotary switch for each position listed on the table .
Table 1
Rotary Dial Position Check the Resistance Between the Following Contacts on the Switch.
1 Contact (1) to Contact (2)
3 Contact (1) to Contact (3)
7 Contact (1) to Contact (4)
10 Contact (1) to Contact (5) Expected Result:Each resistance measurement is less than 5 ohms.Results:
OK - Each resistance measurement is less than 5 ohms. The switch is correct. Proceed to Test Step 3.
NOT OK - A resistance measurement is greater than 5 ohms. The resistance measurement is not correct. There is an open circuit in the switch.Repair: Replace the switch.STOPTest Step 2. INSPECT THE HARNESS CONNECTIONS.
The disconnect switch and the key start switch remain in the OFF position.
Inspect the harness connections. Make sure that the connectors are clean and that the connectors are tight.
Check the mating of the harness connectors.
Check wires at the connector.
Check each wire for nicks or signs of abrasion in the insulation.
Check for moisture at the connector.
Check for dirty contacts or corroded contacts.
Check each pin and each socket. Expected Result:The machine harness connectors are tight and free of corrosion. Results:
OK - The machine harness connectors are tight and free of corrosion. Proceed to Test Step 4.
NOT OK - The machine harness connectors are NOT tight or NOT free of corrosion. Repair: Repair or replace the machine harness.STOPTest Step 3. CHECK THE HARNESS FOR AN OPEN CIRCUIT.
The disconnect switch and the key start switch remain in the OFF position.
Disconnect the J1 and J2 machine harness connectors from the Machine ECM.
Use the following table for the placement of a jumper wire to the connector for the switch. Check the corresponding resistance for the contacts of the machine harness connectors.
Table 2
Jumper Location on the Connector for the Switch Connectors on the Machine Harness
Contact (1)
to
Contact (2) Contact J1-10 (wire A755-PK(Pink)) and contact J1-2 or J1-14 (wire 235-BK(Black)) of the machine harness.
Contact (1)
to
Contact (3) Contact J1-19 (wire A756-BU(Blue)) and contact J1-2 or J1-14 (wire 235-BK(Black)) of the machine harness.
Contact (1)
to
Contact (4) Contact J1-20 (wire A757-GY(Grey)) and contact J1-2 or J1-14 (wire 235-BK(Black)) of the machine harness.
Contact (1)
to
Contact (5) Contact J1-11 (wire A758-BR(Brown)) and contact J1-2 or J1-14 (wire 235-BK(Black)) of the machine harness. Expected Result:The resistance measurements are all less than 5 ohms.Results:
OK - The resistance measurements are all less than 5 ohms. The machine harness is correct. Proceed to Test Step 4.
NOT OK - A resistance measurement is greater than 5 ohms. The resistance measurement is not correct. There is an open circuit in the machine harness.Repair: Repair, or replace, the machine