5033846 JOHNSON HOUSING

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C-10 and C-12 enginesLeft side engine view
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C-15 enginesLeft side engine viewIf a replacement of the ECM is required, the ECM parameters and the timing calibration can be transferred from the suspect ECM to the replacement ECM. Timing calibration will NOT be necessary. This feature requires the Caterpillar Electronic Technician (Cat ET) and this feature is only possible if the existing ECM can communicate with Cat ET. Use the "Copy Configuration - ECM Replacement" feature on Cat ET.The primary engine speed/timing sensor is connected to the ECM through the engine harness connector J2/P2:48 (Primary Engine Speed/Timing Positive) and J2/P2:49 (Primary Engine Speed/Timing Negative). The secondary engine speed/timing sensor is connected to the ECM through engine harness connector J2/P2:58 (Secondary Engine Speed/Timing Positive) and J2/P2:59 (Secondary Engine Speed/Timing Negative).When the sensors are being installed, complete all of the following tasks:
Lubricate the O-ring with oil.
Ensure that the sensor has a connector face seal inside the connector body. If a seal is damaged or missing, replace the seal.
Ensure that the sensor is fully seated into the engine before tightening the bracket bolt.
Ensure that the connector is latched on both sides.
Ensure that the harness is properly secured, and ensure that the tie-wraps are placed in the correct location.
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Schematic for engine speed/timing sensors
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P2 ECM connectorTest Step 1. Check for Diagnostic Codes
Connect Cat ET to the data link connector.
Turn the key switch to the ON position.
Check for one of the following logged diagnostic codes or active diagnostic codes:
22-11 Primary to Secondary Engine Speed Signal Calibration
64-12 Secondary Engine Speed loss of signal
190-12 Primary Engine Speed loss of signalNote: If the diagnostic code is logged but not active, run the engine until the engine is at normal operating temperature. The problem may only occur when the engine is at the normal operating temperature. If the engine will not start, monitor the engine rpm on Cat ET while the engine is being cranked. Cat ET may need to be powered from another battery while the engine is being cranked. This is done in order to ensure that Cat ET does not reset.Expected Result:One or more of the diagnostic codes that are listed above are logged or active.Note: If you have been directed here from Troubleshooting, "Troubleshooting without a Diagnostic Code" for the following reason, select "No Engine rpm":
The engine rpm was not indicated on Cat ET.Results:
64-12, 190-12 or 22-11 - There is an active diagnostic code or a logged diagnostic code. Proceed to Test Step 3.
Not OK - If none of the codes that are listed are active diagnostic codes or logged diagnostic codes and the engine is not running properly, refer to the appropriate symptoms in the service manual.STOP
No Engine rpm - Engine rpm is not indicated on Cat ET. Proceed to Test Step 2.Test Step 2. Check the Installation of the Sensors and the Bracket
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Flange of the sensor and mounting bracket
The flange of the sensor should be flush against the engine in order to ensure proper operation.
Inspect the bracket in order to ensure that the installation allows the flange of the sensor to be flush against the engine.Verify that the bracket is not bent.Note: The bracket cannot be replaced separately.
Ensure that one O-ring has been installed on the sensor, and ensure that the O-ring is free of damage.
If the following diagnostic code is active, there may be a problem with the assembly of the engine:
22-11 Primary to Secondary Engine Speed Signal Calibration Refer to Illustration 5.Expected Result:The sensors and the bracket are properly installed.Results:
OK - The sensors and the bracket are properly installed. Proceed to Test Step 3.
Not OK - Repair: Perform the following procedure in order to properly install the sensors and the bracket:
Loosen the bolt that holds the sensor mounting bracket to the engine.
Seat the sensor and tighten the bolt.If the sensor will not seat, repair the sensor or replace the sensor, as required.Note: The sensor must not be removed from the bracket.
Ensure that the sensor is properly oriented and that