Volvo All Engines (2010 Emissions) Fault Code: SPN 91 FMI 2 PID: 91 Accelerator Pedal Position 1

The pedal message is used to calculate fuel injection.
The J1587 and J1939 serial data lines are used as the standard communication link for on-board vehicle instrumentation, off-board service diagnostics and fleet management.
The (VECU) Vehicle Electronic Control Unit is linked to the Engine Control Module (ECM) via these data lines.

Conditions for diagnostic trouble code (DTC):
1) Functional disturbance, idle validation switches
2) Accelerator pedal sensor value changes and there is no change in idle validation switch value, or vice versa.

Observable symptoms
1) Missing kick-down effect
2) The engine does not respond when accelerator pedal is pressed.

Probable cause
1) Accelerator pedal, Sensor
2) Wiring harness
3) Short circuit
4) Open circuit
5) Idle validation switch