C4.4 and C6.6 Industrial Engines and Engines for Caterpillar Built Machines Caterpillar

The Electronic Control Module (ECM) detects a position for the throttle switch that has not been defined.

System Response:

If equipped, the warning lamp will come on. The diagnostic code will be logged.

The engine will use the primary throttle until the fault is repaired.

If the primary throttle has a fault, the following conditions will occur:

• The engine will default to the limp home speed.

• If the engine speed is higher than the limp home speed, the engine will decelerate to the limp home speed.

• If the engine speed is lower than the limp home speed, the engine speed will remain at the current speed.

• The engine will remain at this speed while the diagnostic code remains active.

• All inputs from the faulty throttle are ignored by the ECM until the fault is repaired.

• All inputs from the repaired throttle will be ignored by the ECM until the keyswitch has been turned to the OFF position and then back to the ON position.

Test Step 1. Perform the following diagnostic procedure: Throttle Switch Circuit - Test

Results:

• OK - STOP