ELBOW-OUTLET 6I1575 - Caterpillar

Conditions Which Generate This Code:The Bus Transformer Box (BTB +) reduces the AC line to neutral voltages of phase A and phase C from the bus to usable signal levels for the GSC+P. The GSC+P uses these reduced signals for detecting the phase sequence of the bus. The GSC+P will utilize the signal of phase A in order to measure the amplitude of the voltage on the bus. The GSC+P will utilize the signal of phase C in order to measure the frequency of the voltage on the bus.The possible cause of a cid 1170 fmi 04 diagnostic code is an open neutral connection to the input of the BTB +, causing a phase angle of approximately 180°.Test Step 1. CHECK THE VOLTAGE OF THE INPUTS TO THE BUS TRANSFORMER BOX (BTB +)
Illustration 1 g00603288
Bus transformer box
Turn the engine control switch (ECS) to "STOP".
Locate the input wires of the BTB +.
Start the engine and run the engine at rated speed.
Close the breaker in order to energize the bus.
Measure the voltage from phase A to the neutral lead and measure the voltage from phase C to neutral lead. Make note of the voltages.
Measure the voltage from Phase A to Phase B.
Compare the voltages measured in the previous two steps.Expected Result:The voltage measured from Phase A and Phase C to the neutral lead should be greater than 55% to 60% of the voltage measured from Phase A to Phase B.Results:
OK - The voltage measured from Phase A and Phase C to the neutral lead is greater than 55% to 60% of the voltage measured from Phase A to Phase B. Proceed to Test Step 2.
NOT OK - The voltage measured from Phase A and Phase C to the neutral lead is NOT greater than 55% to 60% of the voltage measured from Phase A to Phase B.Repair: The neutral wire is open. Use the System Schematic for the BTB + and the AC schematic in Testing And Adjusting, "Schematics And Wiring Diagrams" section to troubleshoot the wiring and find the exact cause of the diagnostic code.STOPTest Step 2. CHECK VOLTAGE ON GSC+P INPUT.
Stop the engine. Turn the engine control switch (ECS) to "STOP".
Install cable probes on the GSC+P 40 pin connector contacts 17 and 18.
Start the engine and run the engine at rated speed.
Close the breaker in order to energize the bus.
On the GSC+P, measure the voltage from connector contact 17 to battery negative, and from connector contact 18 to battery negative. Make note of the voltages.
Measure the voltage between GSC+P connector contact 17 and GSC+P connector contact 18. Make note of the voltages.
Compare the voltages measured in the previous two steps.Expected Result:The voltage measured from contact 17 and 18 to battery negative should be greater than 55% to 60% of the voltage measured between contact 17 and contact 18.Results:
OK - The voltage measured from contact 17 and 18 to battery negative is greater than 55% to 60% of the voltage measured between contact 17 and