VALVE GP-CONTROL 9V4335 - Caterpillar

System Operation Description:Use this procedure if another procedure has made reference to this procedure. Also use this procedure under the following circumstances:
Failure of the power supply to the starting aid
A failure of the starting aidThere are two types of starting aid that equip 3000 Series engines. The 3054E engine uses glow plugs. The 3056E engine uses an air inlet heater.The starting aid is used to improve the engine starting when the engine is cold. A reduction of white smoke is also a benefit of the starting aid.The Electronic Control Module (ECM) uses a relay to control the operation of the starting aid.
Illustration 1 g01331434
Schematic for the starting aid (31 pin MIC)
Illustration 2 g01331436
Schematic for the starting aid (70 pin MIC)
Illustration 3 g01625066
ECM pin location for starting aid
(43) Starting aid control
Illustration 4 g01625067
Pin locations for the starting aid on the 31 pin Machine Interface Connector (MIC).
(7) Starting aid control
Illustration 5 g01331433
Pin locations for the starting aid on the 70 pin Machine Interface Connector (MIC).
(43) Starting aid control Test Step 1. Inspect Electrical Connectors and Wiring
Thoroughly inspect the J1/P1 ECM connector and J20/P20 MIC. Inspect the terminal connections on the starting aid relay. Refer to Troubleshooting, "Electrical Connectors - Inspect" for details.
Perform a 45 N (10 lb) pull test on each of the wires in the ECM connector that are associated with the starting aid. Refer to Illustration 3 and 5.
Check the ECM connector (Allen head screw) for the correct torque of 6.0 N m (55 lb in).
Check the harness and wiring for abrasion and for pinch points from the sensors to the ECM. Expected Result:All connectors, pins and sockets should be completely coupled and/or inserted and the harness and wiring should be free of corrosion, abrasion or pinch points.Results:
OK - There are no faults in the wiring and the connectors. Proceed to Test Step 2.
Not OK - There is a fault in the wiring and the connectors.Repair: Perform the following repair:Repair the connectors or wiring and/or replace the connectors or wiring. Ensure that all of the seals are properly in place and ensure that the connectors are completely coupled.Verify that the repair eliminates the fault.STOPTest Step 2. Check the Power Circuit of the Starting Aid Relay
Turn the keyswitch to the ON position.
Measure the voltage between the following contacts:
Terminal A and the battery - terminal
Terminal B and the battery - terminalExpected Result:The battery voltage should be more than 11.0 Volts DC for a 12 Volt system.The battery voltage should be more than 22.0 Volts DC for a 24 Volt system.Results:
OK - The voltage is within limits. Proceed to Test Step 3.
Not OK - The voltage is below limits between terminal A and the battery