3516B Engine for 994F and 994H Wheel Loaders Caterpillar

Timing - Calibrate

Usage:

994F 442

Use this procedure if a problem is suspected with the engine speed/timing or if the diagnostic code in Table 1 is active.

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Table 1
Diagnostic Codes Table
Code	Conditions which Generate this Code	System Response
261-13 Engine Timing Calibration : Calibration Required	The engine speed/timing sensor has not been calibrated.	This will not keep the engine from running. The fuel injection timing may be out of adjustment.

The engine speed/timing sensor is calibrated through a two-step process. A new timing reference is calculated first. The reference is based on the signals from the transducer and the engine speed/timing sensor. Next, the new timing reference is programmed into the permanent memory of the engine's Electronic Control Module (ECM).

The engine speed/timing sensor provides engine information to the ECM. The ECM powers the engine speed/timing sensor with 12.5 ± 1.0 VDC. The sensor senses the tooth pattern on the timing reference gear that is attached to the left camshaft. As the timing gear rotates past the engine speed/timing sensor, a signal is generated in the sensor. This signal is sent to the ECM. The ECM uses this signal in order to calculate the engine position and the engine speed.

A loss of the engine speed/timing signal causes the ECM to stop sending power to the fuel injectors.

Install the Timing Calibration Probe.
1. Turn the keyswitch to the OFF position.
2. Remove the timing calibration plug from the flywheel housing.
3. Examine the flywheel through the timing calibration hole. Ensure that the probe is not inserted into the timing pin hole. If necessary, rotate the engine crankshaft.
4. Install the 6V-3093 Transducer Adapter into the hole for the timing calibration at the flywheel.
5. Insert the 6V-2197 Magnetic Transducer through the 6V-3093 Transducer Adapter. Insert the transducer until contact is made with the surface of the flywheel. Move the transducer 0.9 mm (0.04 inch) away from the flywheel.
  
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  NOTICE
  
  Do not install the timing calibration probe over the timing pin hole at the flywheel or damage will result.
6. Tighten the nut on the 6V-3093 Transducer Adapter.
7. Connect the 7X-1695 cable from the engine timing calibration probe to the connector P26.
8. Start the engine. Allow the engine to exit cold mode operation.
9. Resolve any diagnostic codes in addition to the 261-13.
Calibrate the Fuel Injection Timing.
1. Select "Calibrations" from the "Service" menu on Caterpillar Electronic Technician (ET). Select the "Timing Calibration" from the "Calibrations" menu.
  Note: Engine speed will be set to 800 rpm by the ECM during the calibration.
2. Follow the instructions on the Cat ET screen.
  Note: If the Cat ET screen reads "Could Not Calibrate", the timing has not been set. Verify that the engine speed was stable during the testing (± 50 rpm). If the engine speed was unstable or the engine speed could not be controlled within ± 50 rpm because of mechanical factors or electrical factors, refer to the diagnostic procedure Troubleshooting, "Engine Misfires, Runs Rough or Is Unstable".
  If all of the problems have been corrected but the timing can not be calibrated, check the cable of the 189-5746 Speed Sensor. Check the 189-5746 Speed Sensor in order to verify that the probe is not bent. Verify that the probe is installed correctly before restarting this procedure.