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 pressed down more than 50?%
2) Short circuit to ground on A14.EB:15
3) Open circuit between ECM: Engine Control Module (ECM) and Vehicle Control Unit (VECU)
Observable symptoms
1) The limp home mode does not function
2) Yellow check lamp illuminated
Probable cause
1) Open circuit on signal wire
2) Connector
3) Accelerator pedal
4) Engine control module (ECM)
-
2021 VOLVO PREMIUM TECH TOOL PTT V2.8.21 VCADS+DEVELOPER TOOL+APCI 2021/09 ( 1 PC )
Trucks software $85.00
Related products
-
Allison 1000 & 2000 Gen 5 Fault Code:P2761 TCC PCS Control Circuit Open
1000 & 2000 Gen 5 -
Allison 1000 & 2000 Gen 5 Fault Code:U0100 Lost Communication With ECM A
1000 & 2000 Gen 5
-
Detroit DD13 EPA07 (2007-09) Fault Code: SPN 558 FMI 3 (CPC) Open Circuit
DD13 EPA07 (2007-09) -
PACCAR MX (2004 Emissions) Fault Code: P1601 PCI ECU – Internal Error
MX (2004 Emissions)