The Idle Validation Switch is open at the idle position and transmits no voltage to the (VECU) Vehicle Electronic Control Unit. At approximately 1-13% pedal position the Idle Validation Switch closes and completes the circuit to the (VECU) Vehicle Electronic Control Unit.
The (VECU) Vehicle Electronic Control Unit then sends a voltage signal to the Engine Control Module (ECM) indicating accelerator pedal position. If both communication links (J1939, J1587) are faulty the pedal demand functionality enters limp-home. During limp-home the (IVS) Idle Validation Switch is used for ramping requested torque.
Conditions for diagnostic trouble code (DTC):
1) Accelerator pedal (AP) released
2) Short circuit to battery voltage on A14.EB:15
Observable symptoms
1) The limp home mode does not function
2) Yellow check lamp illuminated
Probable cause
1) Short circuit to voltage supply, signal wire
2) Connector
3) Accelerator pedal
4) Engine control module (ECM)
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