SCREW 1783339 - Caterpillar

Conditions Which Generate This Code:
Illustration 1 g00681895
System Schematic For Electronic Governor Relay (EGR)
Illustration 2 g00681904
System Schematic For Ignition Shutoff RelayThe purpose of the CID 0566 is to alert the operator that the GSC+ did not control the engine shutdown. A shutdown fault initiated solely by the engine ECM will result in a CID 566 diagnostic code on the GSC+. The GSC+ normally controls all engine shutdown functions for both normal operation and fault shutdowns. If an outside influence causes an engine shutdown, the GSC+ shows a CID 0566. There is only one failure mode for a CID 0566. This failure mode is FMI 07. FMI 07 is an improper mechanical response.The diagnostic code causes the following sequence of events:
On a running engine, the GSC+ detects that engine speed has dropped from rated speed to 0 rpm when the GSC+ has not called for a shutdown.
The GSC+ determines that no engine speed sensor fault is present that explains the drop in speed signal.
The GSC+ declares a CID 0566 FMI 07 and disables the engine from running or starting.The possible cause of a CID 0566 FMI 07 is listed below.
A component that is not under the control of the GSC+ has caused an engine shutdown.The GSC+ treats a CID 0566 FMI 07 as a shutdown fault. Clear the fault from the fault log after troubleshooting is complete.Note: This procedure requires many voltage measurements during simulated engine cranking. The starting motor fuse "F4" on the relay module is removed in order to prevent activating the starting motor and actual engine cranking does not occur. Voltage measurements must be made quickly before the total cycle crank time (setpoint P017) elapses. The total cycle crank time is 90 seconds. See Systems Operation, "Engine/Generator Programming OP5-0". If a measurement of the voltage takes more than 90 seconds, the GSC+ shows an overcrank fault. The overcrank shutdown indicator will FLASH. In order to continue with a voltage measurement, the overcrank fault must be reset by turning the engine control switch (ECS) to OFF/RESET. Then, turn the ECS to START.Test Step 1. PERFORM AN INITIAL CHECK.
Make sure that there are NO OTHER ACTIVE FAULTS. This means that there are no diagnostic codes which are showing on the upper display. This means that no shutdown or alarm indicators are flashing. Failure to do so may result in erroneous troubleshooting and needless replacement of parts. The operator will make many voltage measurements while the GSC+ is attempting to crank the engine. If the GSC+ detects other faults, it will prevent starting by shutting off the fuel and air to the engine. The resulting voltage measurements would then be the exact opposite of the voltage which is expected in the procedures.
Check the fuel level and quality.
Check for a plugged fuel filter.
Check for a plugged air filter.
Refer to the Service Manual for the engine if there is an obvious fault with the engine or the fuel system.
Check the operation of