Massey Ferguson 10.00.25 – AC Module (AIRCON): No Vehicle Speed Information Received On The CAN BUS To AC Module (AIRCON)

The Air Conditioning system uses the vehicle's speed signal to adjust climate control parameters based on how fast the tractor is moving. This code sets when the AC module stops receiving the vehicle speed data packets from the network, which are typically broadcast by the Transmission Control Unit (TCU) or Engine Control Unit (ECU).

• 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
• 4707
• 4708
• 4709
• 4710
• 5608
• 5609
• 5610
• 5611
• 5612
• 5613
• 7614
• 7615
• 7616
• 7618
• 7619
• 7620
• 7622
• 7624
• 7626

1. 1

   Check the speedometer/dash while driving: if the speedometer reads 0 km/h while moving, the root cause is a failed Vehicle Speed Sensor (VSS) or TCU issue, not the AC module.

2. 2

   Scan for global CAN faults using a diagnostic tool to check if other modules (like the Engine ECU or Dash) are also missing the speed signal.

3. 3

   If only the AC module has this code, inspect the AC module connector and wiring harness (usually in the cab roof console or side pillar) for rodent damage, chafing, or loose pins.

4. 4

   Test CAN bus voltage at the AC module connector using a multimeter (verify CAN High is 2.5V to 2.7V and CAN Low is 2.3V to 2.5V).

1. 1

   Disconnect Power

   Turn off the ignition and disconnect the negative battery terminal to prevent electrical spikes.

2. 2

   Address Global Speed Issues (If Applicable)

   If the speedometer was dead during diagnostics, locate the Vehicle Speed Sensor on the side of the transmission housing. Inspect its pigtail connector for corrosion. If damaged, repair the wiring; if intact, replace the VSS.

3. 3

   Address Isolated AC Module Issues

   If the speed signal is present everywhere except the AC module, access the rear of the AC control panel.

4. 4

   Clean and Reseat

   Disconnect the main harness to the AC module. Spray the pins with electrical contact cleaner, ensure no pins are pushed back into the plastic housing, and firmly reconnect it.

5. 5

   Repair CAN Wiring

   If you found broken CAN wires during the diagnostic phase, strip the damaged section, solder in a new piece of wire (ensuring the CAN wires remain twisted at the same pitch to prevent electromagnetic interference), and seal with heat shrink.

6. 6

   Replace the AC Module

   If the wiring is perfectly intact, the CAN bus has continuity, and the speed signal is verified on the network but the code persists, the CAN transceiver inside the AC module has failed. Replace the AC control unit.

7. 7

   Clear and Test

   Reconnect the battery, use a diagnostic scanner to clear the 10.00.25 fault code, and test drive the tractor to ensure the code does not return.