| 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.
| |
| 图 1 | g03850320 |
注: 2 and 8 codes are detecting an open circuit or short circuit of the sensor or the harness.
注: 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
| 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 issues could occur if the resistor is not properly secured. |
Resistor |
Result: The resistor is OK Proceed to Test Step 2 Result: The resistor is NOT OK. Make the necessary repairs. |
2. Check Resistance of 1150Ω Resistor |
Resistor |
Result: The resistor is OK. Result: The resistor in NOT OK. Proceed to Test Step 3. |
3. Check Supply Voltage at the Sensor Connector A. Turn the keyswitch to ON. B. Disconnect the crankshaft position sensor. Measure the voltage between 5VDC supply terminal and ground terminal on the harness. The voltage should be 5V. |
5 VDC |
Result: The voltage was OK. Proceed Test Step 4. Result: The voltage was NOT OK. There is a problem in the wiring harness. Refer to Special Instruction, REHS7774for jumper harnesses that are available for the engine connector. Refer to Special Instruction, REHS7297 for engine ECM connector repair options. Verify that the problem is resolved. |
4. Remove the Sensor A. Are there signs of contact with the sensor or magnetic material. |
Sensor |
Result: There is no signs of contact. Proceed to Test Step 5. Result: There are signs of contact. Repair: Determine the root cause and replace the sensor. |
5. Crankshaft and Camshaft Pulsar Gear A. Check the crankshaft and camshaft pulsar gears for damage B. Check that the crankshaft and camshaft pulsar gears are torqued to specification. |
Pulsar Gear |
Result: The pulsar gear is OK. Result: The pulsar gears are NOT OK. Make the necessary repairs. |
If this procedure did not correct the issue, contact your Technical Communicator (TC).