COWLING GP 4Z7276 - Caterpillar

Table 1
Diagnostic Trouble Code for Cooling Fan - Calibrate
CDL Code Code Description Comments
1551-13 Engine Demand Fan System out of calibration The fan speed is not calibrated to the fan control solenoid.
The code is logged. The Electronic Control Module (ECM) supplies current to the engine fan control solenoid. The engine fan control solenoid controls the pressure to the fan pump by allowing oil to bypass the fan pump. The fan pump drives the fan. For accuracy, the ECM must determine the relationship between the current to the engine fan control solenoid and the actual fan speed. The electronic service tool is used to calibrate the current to a known fan speed.Note: The ECM will use a nominal current to drive the engine fan control solenoid on the initial calibration. The ECM uses the last calibrated value as the starting point on subsequent calibrations.
Table 2
Required Tools
Tool Part Number Part Description Qty
A 348-5430 Multi-Tool Gp 1
B 308-7264 Multitach Tool Gp 1
Table 3
Troubleshooting Test Steps Values Results
1. Calibrate the Cooling Fan Speed
A. Connect the electronic service tool to the diagnostic connector.
B. Select the "Service" tab and select "Calibrations". Start the "Fan Calibration". Meet the required conditions to proceed with the calibration. Follow the directions that are provided on the electronic service tool.
Note If the machine has automatic fan calibration, the "Fan Calibration" option will not be available in electronic service tool.
C. Use Tooling (A), Tooling (B), and Software License, NETG5044 to measure actual fan speed.
Fan speed
Result: The actual fan speed does not match the fan speed on the electronic service tool.
Repair: Adjust the current to change fan speed.
Use the electronic service tool to clear all logged diagnostic codes. Verify that the repair eliminates the fault.
Result: The actual fan speed matches the fan speed on the electronic service tool.
Press the "Next" button.
Follow the directions that are provided on the electronic service tool to complete the calibration.