System Operation Description:
The data radio is not receiving power.
The probable conditions that cause this symptom are in the following list:
- Display is not turned "ON".
- A fuse is open or a circuit breaker is open.
- Failed data radio
- Power Jumper
- Power Module
- Damaged harness or connector
Test Step 1. VERIFY THAT THE DISPLAY WILL TURN ON.
- Ensure that the battery disconnect switch and the key start switch are in the ON position.
- Turn the display ON.
Expected Result:
The display turns ON.
Results:
- OK - The display turns ON. Proceed to Test Step 2.
- NOT OK - The display does not turn ON.
Repair: Refer to the Troubleshooting section of Service Manual, KENR8980, "Electrical Power Supply (Display)".
STOP
Test Step 2. VERIFY THAT THE DATA RADIO POWERS UP.
- Verify that the power LED on the data radio is illuminated.
Expected Result:
The power LED on the data radio is illuminated.
Results:
- OK - The power LED on the data radio is illuminated.
Repair: The cause of the problem was Display. The Display was turned Off. Return the machine to service.
STOP
- NOT OK - The power LED on the GPS receiver(s) is not illuminated. Proceed to Test Step 3.
Test Step 3. CHECK THE POWER TO THE GPS RECEIVERS.
- Disconnect the harness connectors from the connector for the data radio.
- Measure the voltage between pin 1 and pin 2 on the harness connector for the data radio.
Expected Result:
The measured voltage is approximately machine voltage.
Results:
- OK - The measured voltage is approximately machine voltage.
Repair: The data radio has failed. Replace the failed AccuGrade radio.
STOP
- NOT OK - The voltage is not approximately machine voltage. Proceed to Test Step 4.
Test Step 4. CHECK FUSE OR CIRCUIT BREAKER.
- Check the fuse or the circuit breaker.
Note: Use the schematic for your machine in order to identify the correct fuse or the circuit breaker.
Expected Result:
The fuse or the circuit breaker is okay.
Results:
- OK - The fuse or the circuit breaker is okay. Proceed to Test Step 5.
- NOT OK - The fuse or the circuit breaker has failed.
Repair: Replace the fuse or the circuit breaker.
STOP
Test Step 5. CHECK FOR AN OPEN POWER JUMPER IN THE POWER CIRCUIT IN THE HARNESS.
- Use the electrical schematic for the machine in order to determine if a power jumper is used.
- Disconnect the power jumper.
- Place a jumper between pin B and pin C at the harness connector of the Display.
- Turn the Display ON.
Expected Result:
The data radio powers up.
Results:
- OK - The power jumper has failed.
Repair: Replace the power jumper.
STOP
- NOT OK - The data radio does not power up. The power jumper is not the cause of the failure. Proceed to Test Step 6.
Test Step 6. CHECK FOR A SHORTED POWER CIRCUIT IN THE HARNESS.
- Check the harness for the Display for a short circuit condition.
Note: Use the schematic for your machine in order to identify the wiring for the power circuit.
Expected Result:
A short circuit condition is not present in the harness.
Results:
- OK - A short circuit condition is not present in the harness. Proceed to Test Step 7.
- NOT OK - A short circuit condition is present in the harness.
Repair: Repair the harness or replace the harness.
STOP
Test Step 7. CHECK FOR AN OPEN POWER CIRCUIT IN THE HARNESS.
- Check the harness for the Display for an open circuit condition.
Note: Use the schematic for your machine in order to identify the wiring for the power circuit.
Expected Result:
An open circuit condition is not present in the harness.
Results:
- OK - An open circuit condition is not present in the harness. The power module (if equipped) has failed.
Repair: Replace the power module.
STOP
- NOT OK - An open circuit condition is present in the harness.
Repair: Repair the harness or replace the harness.
STOP