WIRING GP-PAYLOAD 5076010 - Caterpillar

Operation Description:Use this procedure if a 1551-13 Engine Demand Fan System : Calibration Required is active.This code indicates that the cooling fan system has not been calibrated.The wiring from the Electronic Control Module (ECM) to the engine cooling fan does not include a feedback circuit in order to detect the speed of the cooling fan. For this reason, the speed of the engine cooling fan needs to be calibrated. The following procedure is performed in order to calibrate the current that is sent to the solenoid for the engine cooling fan from the ECM.During the calibration, a 1U-6602 Photo-Tachometer is used in order to determine the actual speed of the fan. The current to the solenoid is adjusted using Caterpillar Electronic Technician (ET). The ECM uses a min/max setting to provide the correct offset for the entire speed range of the cooling fan.Ensure that the following conditions are met before the calibration procedure is performed:
The parking brake is engaged.
The engine speed is set to high idle.
The engine coolant temperature is at least 75 °C (167 °F).
No diagnostic codes are active.Test Step 1. Use Cat ET to Calibrate the Fan Speed
Ensure that the keyswitch is in the OFF position.
Secure a strip of reflective tape to the fan in a place that is convenient for use of the photo-tachometer.
Connect the 1U-6602 Photo-Tachometer. Refer to Tool Operating Manual, NEHS0554 for information that is related to the operation of the photo-tachometer.
Connect Cat ET to the service tool connector. Refer to Troubleshooting, "Electronic Service Tools".
Turn the keyswitch to the ON position.
Start the engine. Set the engine speed to high idle.
Select the following menu options on Cat ET:
"Service"
"Calibration"
"Engine Cooling Fan Calibration"
Follow the instructions that are provided:
Ensure that both of the min/max settings for the desired fan speed in Cat ET match the reading that is provided by the photo-tachometer.Expected Result:The desired fan speed in Cat ET matches the speed that is reported by the photo-tachometer. The engine cooling fan speed is calibrated.Results:
OK - The engine cooling fan speed is calibrated.STOP
Not OK - The engine cooling fan speed is not calibrated. Perform the calibration procedure again.Repair: If Cat ET is not communicating with the ECM refer to Troubleshooting, "Electronic Service Tool Will Not Communicate with ECM".STOP