What are SPN 2011 FMI 9 and SPN 973 FMI 9 codes and how to fix them?

If you own a Freightliner Cascadia truck, you may encounter some codes on your dashboard that indicate a problem with your engine or your control module. Two of these codes are SPN 2011 FMI 9 and SPN 973 FMI 9. In this article, we will explain what these codes mean, what causes them, and how to troubleshoot and fix them.

What are SPN 2011 FMI 9 and SPN 973 FMI 9 codes?

SPN stands for Suspect Parameter Number, which is a numerical code that identifies a specific parameter in the engine or the control module. FMI stands for Failure Mode Identifier, which is a numerical code that indicates the type of failure or fault in the parameter. For example, FMI 9 means that the parameter is not available or not responding.

SPN 2011 FMI 9 means that the engine retarder selection signal is not available or not responding. The engine retarder is a device that helps to slow down the vehicle by reducing the engine power. The engine retarder selection signal is a signal that tells the engine control module (ECM) which mode of engine retarder to use. There are three modes of engine retarder: low, medium, and high.

SPN 973 FMI 9 means that the engine control module (ECM) / common powertrain controller (CPC4) message is not available or not responding. The ECM is the computer that controls the engine functions, such as fuel injection, ignition, and emission control. The CPC4 is another computer that communicates with the ECM and other modules in the vehicle, such as the transmission, the instrument cluster, and the body controller. The ECM / CPC4 message is a message that contains information about the engine status, such as speed, temperature, and pressure.

What causes SPN 2011 FMI 9 and SPN 973 FMI 9 codes?

There are several possible causes for these codes, such as:

  • A faulty engine retarder switch or wiring
  • A faulty engine retarder solenoid or wiring
  • A faulty engine retarder relay or wiring
  • A faulty ECM or wiring
  • A faulty CPC4 or wiring
  • A software issue in the ECM or the CPC4
  • A communication issue in the CAN bus

The CAN bus is a network of wires that connects the ECM, the CPC4, and other modules in the vehicle. The CAN bus allows the modules to exchange data and commands. If there is a problem in the CAN bus, such as a short circuit, an open circuit, or a bad connection, the modules may not be able to communicate properly, resulting in codes like SPN 2011 FMI 9 and SPN 973 FMI 9.

How to troubleshoot and fix SPN 2011 FMI 9 and SPN 973 FMI 9 codes?

To troubleshoot and fix these codes, you need to follow these steps:

  1. Check for multiple codes. If there are other codes present, such as CPC SPN 168/FMI 0/14/18 (Battery Voltage) or MCM SPN 625/FMI 9 (CAN Bus), you need to troubleshoot and fix those codes first, as they may be related to the problem.
  2. Check the engine retarder switch. The engine retarder switch is located on the steering column or the dashboard. It has three positions: low, medium, and high. Use a multimeter to check the continuity and resistance of the switch and the wiring. If there is an open circuit or a high resistance, replace the switch or the wiring.
  3. Check the engine retarder solenoid. The engine retarder solenoid is located on the engine. It has three wires: a power wire, a ground wire, and a signal wire. Use a multimeter to check the voltage and resistance of the solenoid and the wiring. If there is no voltage or a high resistance, replace the solenoid or the wiring.
  4. Check the engine retarder relay. The engine retarder relay is located in the fuse box. It has four pins: a power pin, a ground pin, a control pin, and a load pin. Use a multimeter to check the voltage and resistance of the relay and the wiring. If there is no voltage or a high resistance, replace the relay or the wiring.
  5. Check the ECM and the CPC4. The ECM and the CPC4 are located in the engine compartment. They have multiple connectors and wires. Use a diagnostic tool to check the software version and the communication status of the ECM and the CPC4. If there is a software issue, update the software using the diagnostic tool. If there is a communication issue, check the connectors and the wires for any damage or corrosion. If there is any damage or corrosion, replace the connectors or the wires.
  6. Check the CAN bus. The CAN bus is a network of wires that connects the ECM, the CPC4, and other modules in the vehicle. Use a diagnostic tool to check the CAN bus for any errors or faults. If there are any errors or faults, use a multimeter to check the voltage and resistance of the CAN bus wires. If there is a short circuit, an open circuit, or a bad connection, repair or replace the wires.

SPN 2011 FMI 9 and SPN 973 FMI 9 are codes that indicate a problem with the engine retarder selection signal or the ECM / CPC4 message. These codes can be caused by a faulty switch, solenoid, relay, ECM, CPC4, wiring, software, or CAN bus. To troubleshoot and fix these codes, you need to check the components and the wires using a multimeter and a diagnostic tool, and replace or repair any faulty parts.

 

Code Possible Cause Solution
SPN 2011 FMI 9 Faulty engine retarder switch or wiring Replace switch or wiring
Faulty engine retarder solenoid or wiring Replace solenoid or wiring
Faulty engine retarder relay or wiring Replace relay or wiring
Faulty ECM or wiring Replace ECM or wiring
Faulty CPC4 or wiring Replace CPC4 or wiring
Software issue in ECM or CPC4 Update software using diagnostic tool
Communication issue in CAN bus Repair or replace CAN bus wires
SPN 973 FMI 9 Faulty ECM or wiring Replace ECM or wiring
Faulty CPC4 or wiring Replace CPC4 or wiring
Software issue in ECM or CPC4 Update software using diagnostic tool
Communication issue in CAN bus Repair or replace CAN bus wires

Leave a Reply

Your email address will not be published. Required fields are marked *