RELIEF VALVE GROUP 8P1672 - Caterpillar

this procedure if the diagnostic code in Table 1 is active.
Table 1
Diagnostic Codes Table
Description Conditions which Generate this Code System Response
261-11 Engine Timing Offset fault The wiring to the sensors has the wrong polarity. The code is logged.
261-13 Engine Timing Calibration calibration required A timing calibration is required for a new engine, replacing an Electronic Control Module (ECM) that fails to communicate or following work on the front gear train, the camshaft, or the crankshaft. The code is logged. If a 261-11 diagnostic code is active, verify that the wiring is installed correctly to the engine speed/timing sensors.The ECM has the ability to calibrate the mechanical differences between the Top Center (TC) of the No. 1 piston and the orientation of the camshaft. The ECM uses the signal from the primary engine speed/timing sensor as a control reference that identifies the exact orientation of the crankshaft. The ECM uses the signal that is detected from the secondary engine speed/timing sensor to identify the exact orientation of the camshaft.The two signals are then used by the ECM to calculate a timing offset. The offset is used by the ECM to calibrate the signal from the secondary engine speed/timing sensor. Note: A timing calibration will not increase the available engine power.
Start the Engine and Check for Diagnostic Codes.
Connect Caterpillar Electronic Technician (ET) to the service tool connector. Refer to Troubleshooting, "Electronic Service Tools".
Start the engine and run the engine until the engine is at the normal operating temperature.
Check for active diagnostic codes. Wait at least 30 seconds in order for the codes to become active. The engine must not have any active diagnostic codes during the timing calibration except for a 261-13 Engine Timing Calibration required.
Calibrate the Timing.
Set the engine speed to 1100 50 rpm. The engine speed must be steady within this rpm range in order for the calibration to be successful.
After the engine has warmed up, access the "Timing Calibration" screen on the Cat ET. Access the following display screens in order:
Service
Calibrations
Timing Calibration
To calibrate the timing, select "Continue" on Cat ET. Wait until Cat ET indicates that the timing is calibrated. Return the engine to service if Cat ET indicates that the timing is calibrated.The following conditions can cause the timing calibration to fail:
The crankshaft and camshaft gears have been reassembled incorrectly.
The engine speed/timing sensors are installed incorrectly.
The engine speed is not correct and the engine speed is unstable. If the engine speed is unstable, refer to Troubleshooting, "Engine Misfires, Runs Rough or Is Unstable".