HOSE 2730321 - Caterpillar

Table 1
Diagnostic Trouble Codes
Code and Description Conditions Notes
636-2
Crankshaft position sensor pulse number error Battery voltage is normal. Sensor supply is normal. Engine is not stalled This occurs ten times or more. Engine is derated.
Warning Level 2
Symptoms are long engine crank before starting and increased engine vibration.
Engine will stop if both crankshaft and camshaft position sensors fail.
636-8
No crankshaft position sensor signal Battery voltage is normal. Sensor supply is normal. Engine is not stalled. Pulse count per rotation is not 56 teeth occurs 10 times or more. No recognition of crankshaft for ten times or more.
636-7
Engine Position Sensor – Large phase shift between Camshaft and Crankshaft position sensors Engine is running. Battery is normal. Sensor supply voltage is normal. Camshaft position sensor signal is normal. Camshaft position sensor signal is normal. Coolant temperature is 10C or higher. Phase difference between crankshaft and camshaft pulse exceeds 15 degrees 10 times or more. Warning Level 2
Symptom is a long engine crank before starting.
723-2
Camshaft sensor Pulse Number Error Battery Voltage is Normal. Sensor supply is normal. Engine speed is 350 rpm or higher. Pulse count rotation is not five teeth. -
723-8
No Input of Camshaft Position Pulse Battery Voltage is Normal. Sensor supply is normal. Engine is not stalled. No recognition of camshaft sensor pulse. None The crankshaft position sensor is the primary speed/timing sensor. The camshaft position sensor is the secondary speed/timing sensor. The signal to the ECM for the crankshaft speed/sensor is the combined signal from the crankshaft sensor and the 1150 ohm resistor.Under normal operation, the secondary engine speed/timing sensor is used to determine timing for starting purposes. The secondary engine speed/timing sensor is used to determine when the piston in the No. 1 cylinder is at the top of the compression stroke. The primary engine speed/timing sensor is then used to determine engine speed and the signal from the secondary camshaft sensor is ignored.If the engine is running and the signal from the primary engine speed/timing sensor is lost, the engine will derate. Loss of the signal from the secondary engine speed/timing sensor during engine operation will not result in any noticeable change in engine performance.During start-up, the loss of either the crankshaft or camshaft speed/timing sensor will result in hard starting.A faulty 1150 ohm resistor will also create a crankshaft speed/timing sensor fault code, resulting in hard starting. Refer to the "Electronic System Overview" for the location.The loss of both the crankshaft and camshaft speed/ timing sensor will result in a no start or the engine will stop.
Illustration 1 g03850320Note: 2 and 8 codes are detecting an open circuit or short circuit of the sensor or the harness.Note: 7 codes measures a large phase shift between the crankshaft position sensor and the camshaft position sensor.For diagnostic codes 636-2 and 636-8 refer to Table 2
Table 2
Troubleshooting Test Step Value Expected Results
1. Check the 1150Ω Resistor on the Engine Harness
Note: Does Not Apply to C3.8 Tier 4 Final Engine Harness.
A. Ensure that the resistor is properly secured with a tie strap. Intermittent