Massey Ferguson 10.00.24 – AC Module (AIRCON): No Engine Speed Information Received On The CAN BUS To AC Module (AIRCON)

This indicates a communication failure on the tractor's Controller Area Network (CAN bus). The Air Conditioning (AC) control module relies on engine RPM data—typically broadcast by the Engine Control Unit (ECU)—to safely regulate the AC compressor clutch engagement and manage fan speeds. When the AC module stops receiving this specific CAN message, it logs this code and will likely disable the AC compressor to prevent damage.

• 7724S
• 5712SL
• 7722
• 7722S
• 5713SL
• 7720S
• 7716
• 7718
• T4
• 7715
• 5710SL
• 7726
• 7726S
• 5711SL
• 7718S
• 7719
• 7714
• 7716S
• 7720
• Tier 4 (2015-2021)
• 7715S
• 7724
• 4700 Series
• 4707
• 4708
• 4709
• 4710
• 5600 Series
• 5608
• 5609
• 5610
• 5611
• 5612
• 5613
• 5700SL Series
• 7600 Series
• 7614
• 7615
• 7616
• 7618
• 7619
• 7620
• 7622
• 7624
• 7626
• 7700 Series
• 7700S Series
• 8600 Series
• 8650
• 8660
• 8670
• 8680
• 8690

1. 1

   Verify Engine RPM on the Dash: Start the tractor and check if the instrument cluster tachometer displays the engine speed. If the dash also shows no RPM, the issue is likely a faulty engine speed sensor or an Engine ECU problem, not the AC module.

2. 2

   Check for Accompanying CAN Codes: Use a diagnostic tool to scan all modules. If multiple modules (Transmission, Dash, Hydraulics) are reporting missing CAN data from the Engine ECU, you have a global CAN bus failure or a dead Engine ECU. If only the AC module has a code, the issue is isolated to the AC module or its specific branch of the CAN wiring.

3. 3

   Inspect AC Module Connectors: Locate the AC module (often in the cab roof or side console). Inspect the main harness connectors (e.g., the blue and yellow connectors noted in the 8600 series manual) for backed-out pins, moisture intrusion, or corrosion.

4. 4

   Test CAN Bus Integrity: Using a multimeter, measure the resistance across the CAN High and CAN Low pins at the AC module connector (with batteries disconnected). It should read approximately 60 ohms. Check for shorts to ground or power on the CAN lines.

1. 1

   Disconnect Power

   Turn off the ignition and disconnect the negative battery cable to prevent electrical shorts.

2. 2

   Access the AC Module

   Remove the interior cab trim panels required to access the Air Conditioning Control Module.

3. 3

   Clean and Reseat Connectors

   Disconnect the wiring harness from the module. Spray the terminals with a high-quality electrical contact cleaner. Ensure no pins are bent or pushed back into the plastic housing. Reconnect firmly.

4. 4

   Repair Wiring (If Applicable)

   If your continuity tests in the diagnostic phase revealed an open or shorted CAN wire between the AC module and the main cab harness splice, trace the wire and repair the break using weather-sealed butt connectors or solder/heat-shrink.

5. 5

   Test the System

   Reconnect the battery, start the engine, and turn on the AC. Clear the fault codes using a diagnostic scanner.

6. 6

   Replace the Module

   If the wiring is perfectly intact, the CAN bus voltages are correct, the Engine ECU is successfully broadcasting speed to other modules, and code 10.00.24 immediately returns, the CAN transceiver inside the AC module has failed. Replace the AC module.