SPN 91 - FMI 19 (Fault Code 297)

SPN91 FMI19

SAE J1939 Multiplexing Accelerator Pedal or Lever Sensor System Error - Received Network Data Error

SAE J1939 Multiplexing Accelerator Pedal or Lever Sensor System

CODES:

Fault Code: 287

PID(P), SID(S): P91

SPN: 91

FMI: 19

Lamp: Red

REASON: SAE J1939 Multiplexing Accelerator Pedal or Lever Sensor System Error - Received Network Data Error. The OEM vehicle electronic control unit (VECU) detected a fault with its accelerator pedal.

EFFECT: Engine may only idle or engine will not accelerate to full speed.

Circuit Description:

Normally, switches, accelerators, and other components are connected to the engine ECM directly through individual wires. Multiplexing allows those same components to be hard wired to an OEM Vehicle Electronic Control Unit (VECU) or Transmission ECU in the cab. Then component values and states from components (such as sensors, accelerators, and switches) can be transmitted from the OEM VECU to the Cummins engine ECM over the SAE J1939 datalink.

Messages sent from OEM VECU's or Transmissions ECU's are received by the Cummins engine ECM and used for controlling the engine. The Cummins ECM and OEM VECU's must be configured properly so that proper operation of the multiplexed components will occur.

Component Location:

The engine ECM is located on the intake side of the engine. The J1939 datalink wiring and VECU location varies by OEM.

Shop Talk:

This fault can occur when the OEM VECU detects an error on the accelerator and or idle validation switch. The ECM has been set up properly (components enabled and OEM VECU source addressed correctly) to receive multiplexed information for the idle validation switch states and accelerator position over the J1939 datalink from an OEM VECU, and the OEM VECU is transmitting the message for that component. The three types of errors that can occur for this fault are:

• When the accelerator is depressed and the OEM VECU reads accelerator position as greater than 0%, but the idle validation switch indicates it is in the idle position. This fault status is transmitted to the Cummins ECM on the J1939 datalink, which causes this fault to occur in the Cummins ECM.

• When the accelerator is released and the OEM VECU reads accelerator position as 0%, but the idle validation switch indicates it is not in the idle position. This fault status is transmitted to the Cummins ECM on the J1939 datalink, which causes this fault to occur in the Cummins ECM.

• The OEM VECU determines that the accelerator signal line is shorted high or shorted low.

NOTE: It is still possible to get a Fault Code 285 or 286 if there is an incorrect setup in the OEM VECU or Cummins ECM, for other components, or the accelerator and idle validation switch, or if the datalink is damaged. OEM configurations must multiplex the accelerator and idle validation switch inputs together to allow the use of the J1939 multiplexing and limp home feature for these components. INSITE™ can be used to monitor multiplexed components.

Read More:

SPN 1347 - FMI 7 (Fault Code 281)

SPN 1043 - FMI 4 (Fault Code 284)

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