TURBO GP-BASIC 0R6871 - Caterpillar

Illustration 1 g01619517
Partial SchematicThe conditions that are listed below may cause the GPS receiver to not power up:
Display
Fuse
Circuit Breaker
Main Power Relay
Wiring
Failed ReceiverTest Step 1. VERIFY THAT THE DISPLAY WILL POWER UP
Ensure that the disconnect switch for the battery and the key start switch are in the ON position.
Turn on the display.Expected Result:The display turns on.Results:
YES - The display turns on. Proceed to Test Step 2.
NO - The display does not turn on.Repair: Perform the procedure that is listed in the Troubleshooting, "Electrical Power Supply (Display)" section of this manual.STOPTest Step 2. VERIFY THAT THE GPS RECEIVER POWERS UP
Verify that the power LED on the GPS receiver is illuminated.Expected Result:The power LED on the GPS receiver is illuminated.Results:
YES - The power LED on the GPS receiver is illuminated.Repair: The problem was because the display was turned off. Return the machine to service.STOP
NO - The power LED on the GPS receiver is not illuminated. Proceed to Test Step 3.Test Step 3. CHECK THE POWER TO THE GPS RECEIVER
Place the disconnect switch and the key start switch in the ON position.
Disconnect the harness connector from the GPS receiver.
Measure the voltage between pin "B" and pin "G" on the harness connector for the receiver.Expected Result:The measured voltage is approximately machine voltage.Results:
YES - The measured voltage is approximately machine voltage. The GPS receiver has failed.Repair: Replace the GPS receiver. Return the machine to service.STOP
NO - The voltage is not approximately machine voltage. Proceed to Test Step 4.Test Step 4. CHECK THE FUSE
Disconnect the 10 amp "AccuGrade" fuse (Fuse 17) from the fuse panel.
Check the resistance across the two contacts of the fuse. Expected Result:The resistance measurement is less than 1.0 ohm.Results:
YES - The resistance measurement is less than 1.0 ohm. The fuse is not open. Proceed to Test Step 5.
NO - The resistance measurement is greater than 1.0 ohms. The fuse is open.Repair: Replace the fuse. Return the machine to operation.STOPTest Step 5. CHECK THE CIRCUIT BREAKERAn open "Main Breaker" circuit will disrupt power to the receiver.
Place the key start switch and the disconnect switch in the OFF position.
Check for an open at the 80 amp "Main Breaker" circuit breaker.Expected Result:The 80 amp "Main Breaker" circuit breaker is open.Results:
YES - The circuit breaker is open.Repair: Reset the open circuit breaker. Resume the operation of the machine.STOP
NO - The 80 amp "Main Breaker" circuit breaker is not open. Proceed to Test Step 6.Test Step 6. CHECK THE MAIN POWER RELAY
Place the disconnect switch and the key start switch in the ON position. The engine should be off.
Measure the voltage between wire (CBL-PU) on the main power relay and frame ground.Expected Result:The voltage measurement is between 18 VDC and 32 VDC.Results:
YES - The voltage measurement is between 18 VDC and 32 VDC. Proceed to Test Step 7.
NO - The voltage measurement is not between 18 VDC and 32 VDC.Repair: Verify that between 18 VDC and 32 VDC is present at the main power relay on wire (CBL-RD) and wire (308-YL). If voltage is not present on