SHAFT-TRACK IDLER 1289693 - Caterpillar

System Operation Description:Use this procedure to troubleshoot the system under the following conditions:
Use this procedure if another procedure has directed you here.
The engine will not start and the electronic service tool indicates a faulty sensor by displaying "Not Detected" against the faulty sensor on the "No Start Parameter" screen.
There is an active diagnostic code or a recently logged diagnostic code that is related to the following:
0190-08 Engine Speed Sensor abnormal frequency, pulse width, or period
0342-08 Secondary Engine Speed Sensor abnormal frequency, pulse width, or period
0261-11 Engine Timing Offset faultThe engine uses two engine speed/timing sensors. The primary speed/timing sensor is located on the left-hand side of the cylinder block close to the flywheel housing. The secondary speed/timing sensor is part of the fuel rail pump. The primary speed/timing sensor generates a signal by detecting the movement of the teeth on the crankshaft timing ring. The crankshaft timing ring is connected to the crankshaft. The signal that is generated by the speed/timing sensor is transmitted to the Electronic Control Module (ECM). The ECM uses the signal from the speed/timing sensor to calculate the position of the crankshaft. The signal is also used to determine the engine speed.The secondary speed/timing sensor is located in the fuel rail pump. The secondary speed/timing sensor generates a signal that is related to the camshaft position. The fuel rail pump is mechanically connected to the camshaft. The secondary speed/timing sensor detects the movement of the teeth on the timing ring in the fuel rail pump. The signal that is generated by the speed/timing sensor is transmitted to the ECM. The ECM calculates the speed and the rotational position of the engine by using the signal. The secondary speed/timing sensor is required for starting purposes.During normal operation, the secondary speed/timing sensor is used to determine the cycle that the engine is on. When the timing has been established, the primary speed/timing sensor is then used to determine the engine speed and the angular position.The loss of signal to the primary sensor and/or the secondary sensor will result in one of the following faults:
A loss of signal from the secondary speed/timing sensor during start-up will prevent the engine from starting.
A loss of signal from the secondary speed/timing sensor during operation of the engine will result in the engine being derated.
The engine will continue to run normally when only the signal from the secondary speed/timing sensor is present.
A loss of signal from both of the sensors during engine operation will cause fuel injection to be terminated and the engine will stop.The primary sensor and the secondary sensor are interchangeable components. If a sensor is suspect, the sensors can be exchanged in order to eliminate a fault. If a secondary sensor is suspect and a replacement secondary sensor is not available, then the primary sensor and the secondary sensor can be exchanged. The exchange will allow testing to determine if the secondary sensor is faulty.
Table 1
P2/J2 Pin Connections    
Function     Sensor Pin     Crankshaft Primary Sensor