G3500 Industrial Engines Caterpillar

Illustration 1	g00664421

There is no signal from the magnetic pickup for the timing control. The crank angle sensor indicates that the engine rpm is greater than 500 rpm and/or the Timing Control Module (TCM) is receiving magneto interface pulses from the Magneto Interface Box (MIB). One of the following conditions exist:

• The signal wire is shorted to the -battery.

• The clearance of the magnetic pickup for the TCM is not correct.

• Metal filings are on the magnetic pickup for the TCM.

• The sensor has failed.

• The clearance for the crank angle sensor is too small.

• There are metal filings on the pickup of the crank angle sensor.

• There are nicks on the flywheel.

System Response:

The engine will not run due to no ignition. No magneto clock signal is sent to the MIB from the TCM. If the signal is not present, the MIB will not fire the magneto. The TCM will activate the outputs for the shutdown and the remote indicator. The "No SPEED SENSOR SIGNAL" LED will illuminate. The code may be viewed on the DDT.

Test Step 1. Perform the following test: Speed Sensor (Short Circuit)

Results:

• OK - Stop.