CM871 and CM876 Electronic Control Systems, ISX and ISM Engines – FAULT CODE 288

SAE J1939 Multiplexing Remote Accelerator Pedal or Lever Position Sensor System – Received Network Data In Error


Overview

CODE REASON EFFECT
Fault Code: 288
PID: P372
SPN: 974
FMI: 2/19
LAMP: Red
SRT: 

SAE J1939 Multiplexing Remote Accelerator Pedal or Lever Position Sensor System – Received Network Data In Error. The OEM vehicle electronic control unit (VECU) detected a fault with the remote accelerator.

The engine will not respond to the remote throttle. Engine may only idle. The primary or cab accelerator may be able to be used.

ISX and ISM – SAE J1939 Multiplexing Remote Accelerator Pedal or Lever
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Circuit Description

Normally, switches, accelerators, and other components are connected to the engine electronic control module (ECM) directly through individual wires. Multiplexing allows those same components to be hard wired to an OEM VECU or transmission electronic control unit (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 the OEM VECU or transmission ECU are received by the Cummins engine ECM and used for controlling the engine. The Cummins ECM and OEM VECU 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. Refer to Procedure 100-002 (Engine Diagrams) in Section E for a detailed component location view. The J1939 datalink wiring and VECU location varies by OEM.

Conditions for Running the Diagnostics

This diagnostic runs continuously when the keyswitch is in the ON position.

Conditions for Setting the Fault Codes

The OEM VECU determines that the remote throttle signal wire is shorted high or shorted low. 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 remote throttle enable switch has a shorted high or shorted low error detected by the OEM VECU. This fault status is transmitted to the ECM on the J1939 datalink, which causes this fault to occur in the ECM.

Action Taken When the Fault Code is Active

  • The ECM illuminates the red STOP ENGINE light immediately when the diagnostic runs and fails.
  • The multiplexed device will not operate.

Conditions for Clearing the Fault Code

The ECM will turn off the red STOP ENGINE light immediately after the diagnostic runs and passes.

Shop Talk

Verify the electronic control module (ECM) calibration is correct. Check the calibration revision history found on QuickServe® Online for applicable fixes to the calibration stored in the ECM. If necessary, recalibrate the ECM. Refer to Procedure 019-032 (ECM Calibration Code) in Section 19 in the corresponding Troubleshooting and Repair Manual for the engine being serviced.

This fault can occur when the OEM VECU detects an error on the remote throttle and or remote throttle enable switch. The ECM has been set up properly (components enabled and OEM VECU source addressed correctly) to receive multiplexed information for the remote throttle enable switch states and remote accelerator position over the J1939 datalink from an OEM VECU, and the OEM VECU is transmitting the message for that component. Most OEMs will not have the circuitry to detect a remote throttle switch error.

The two types of errors that can occur for this fault are:

  • The OEM VECU determines that the remote throttle signal line is shorted high or shorted low. 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 remote throttle enable switch has a shorted high or shorted low error detected by the OEM VECU. This fault status is transmitted to the ECM on the J1939 datalink, which causes this fault to occur in the ECM. Most OEMs will not incorporate fault detection on a switch.

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 remote throttle and remote throttle switch, or the datalink is damaged. The OEM configurations must multiplex the remote throttle and remote throttle switch inputs together to allow the use of the J1939 multiplexing feature for these components. The INSITE™ electronic service tool can be used to monitor multiplexed components.

Refer to Troubleshooting Fault Code t05-288

Last Modified:  09-Jul-2010