HEAD 7F8306 - Caterpillar

Illustration 1 g01873494
Suspension cylinder pressure sensor circuit
This diagnostic code indicates the VIMSTM Application ECM detects the Right Front Strut Pressure sensor signal has an abnormal frequency, pulse width, or period.The output frequency of the sensor changes as the pressure in the suspension cylinder changes. The sensor is powered by the machine electrical system.Note: In addition to the “Suspension Cylinder Pressure Sensor” troubleshooting procedure, the VIMS diagnostics are helpful in troubleshooting other sensors.Use this procedure to troubleshoot the suspension cylinder pressure sensors or any failure associated with the suspension cylinder pressure sensors.Note: This test checks for sensor voltages at the sensor when all the circuits are connected. Unless directed otherwise, do not disconnect any components. Troubleshoot the circuit “as is” before disconnecting any components. Use a calibrated digital multimeter for this procedure.Test Step 1. CHECK THE SENSOR SUPPLY VOLTAGE
Locate the suspect sensor.
Identify the sensor wires and connector contacts. Do not disconnect any harness connectors.
Turn on the keyswitch. The truck can be empty or the truck can be loaded.
At the sensor connector, identify the +V and ground circuits.
Insert 7X-1710 Multimeter Probe leads beside the +V and ground circuit wires in the back of the connector for the sensor .
Measure the voltage. Expected Result:The voltage is between 22.0 DCV and 29.5 DCV.Results:
OK - The voltage is between 22.0 DCV and 29.5 DCV. Proceed to Test Step 2.
NOT OK - The voltage is not between 22.0 DCV and 29.5 DCV.Repair: Trace the +V and ground circuits in the harness. Perform one of the following:
Repair or replace the harness if the harness has failed.
Replace the sensor if the harness has not failed.STOPTest Step 2. CHECK THE SENSOR SIGNAL VOLTAGE
At the sensor connector, identify the signal and ground circuits.
Insert 7X-1710 Multimeter Probe leads beside the signal and ground circuit wires in the back of the connector for the sensor.
Measure the voltage. Expected Result:The voltage is between 1.0 DCV and 9.0 DCV. Results:
OK - The voltage is between 1.0 DCV and 9.0 DCV Proceed to Test Step 5.
NOT OK - The voltage is greater than 9.0 DCV Proceed to Test Step 3.
NOT OK - The voltage is less than 1.0 DCV. Proceed to Test Step 4.Test Step 3. CHECK THE SIGNAL CIRCUIT FOR A SHORT TO +BATTERY
Disconnect the sensor from the harness.
At the harness connector for