Valtra BH Series 140–210 Internal Roll Inertial Sensor Fault – SA 28 SPN 520224 FMI 02

This guide explains how to diagnose and resolve the Valtra BH Series 140–210 internal roll inertial sensor fault, identified by SA 28 – SPN 520224 FMI 02.

❌ Fault Description

Trouble Code:
SA 28 – SPN 520224 – FMI 02

Failure Mode Indicator (FMI 02):
Erratic, intermittent, or incorrect signal

The guidance controller has detected that the signal from the internal roll inertial sensor is outside its normal operating range.

🔍 What Does This Mean?

The guidance controller uses internal inertial sensors to measure vehicle roll and improve steering and guidance accuracy, especially on uneven or sloped terrain.

Important notes:

• The inertial sensors are built inside the guidance controller
• They are not serviceable individually
• If the sensor fails, the entire guidance controller must be replaced

This fault may be caused by:

• Temporary vehicle movement
• Sensor signal instability
• Internal hardware failure of the guidance controller

🚜 Affected Models

• Valtra BH Series 140
• Valtra BH Series 160
• Valtra BH Series 180
• Valtra BH Series 210

🛠️ Diagnosis and Solution

Follow the steps below in order to accurately determine whether the fault is temporary or a true hardware failure.

Step 1: Stop the Vehicle

1. Bring the tractor to a complete stop
2. Park on flat, level ground
3. Leave the vehicle stationary for 5 minutes

This allows the inertial sensor to stabilize and eliminates false movement detection.

Expected Result:
The diagnostic fault code disappears.

Results:

• ✅ YES – The system reported a false diagnostic
  → Proceed to Step 3
• ❌ NO – The fault code remains
  → Proceed to Step 2

Step 2: Repower the Guidance Controller

1. Turn off power to the guidance controller using the appropriate switch
2. Wait 30 seconds
3. Restore power to the guidance controller

Expected Result:
The diagnostic fault code no longer exists.

Results:

• ✅ YES – The system reported a false diagnostic
  → Proceed to Step 3
• ❌ NO – Hardware failure confirmed

Repair Action:
The guidance controller must be replaced according to the customer’s warranty or replacement plan.

🛑 STOP – No further troubleshooting required

Step 3: Report False Diagnostic

If the fault was cleared in Step 1 or Step 2:

1. Report the false diagnostic to AGCO Technical Support
2. Customer may resume normal operation
3. Advise the customer to monitor the system in case the error reappears

🛑 STOP

🔧 Recommended Diagnostic Tools

To diagnose and monitor Valtra and AGCO equipment accurately, we recommend:

• 2025 AGCO EDT (Electronic Diagnostic Tool)
• AGCO 2×4 CANUSB Diagnostic Kit

These tools allow technicians to:

• Read and clear fault codes
• Monitor guidance controller status
• Confirm sensor and controller communication

💬 Need Help with Valtra or AGCO Diagnostics?

If you experience recurring guidance controller errors or need help choosing the right AGCO diagnostic software or interface, Autonumen provides professional technical support and diagnostic solutions.

📧 Email: service@autonumen.com

We’re here to help keep your equipment running accurately and reliably 🚜

Frequently Asked Questions (FAQ)

What does SA 28 – SPN 520224 FMI 02 mean on Valtra BH Series tractors?

This fault code means the guidance controller has detected that the internal roll inertial sensor signal is erratic, intermittent, or outside its normal operating range. The sensor is used to measure vehicle roll and improve guidance accuracy on uneven terrain.

What causes the internal roll inertial sensor fault?

Common causes include temporary vehicle movement, vibration, or instability when the tractor is not on level ground. In some cases, the fault is caused by an internal hardware failure of the guidance controller, where the inertial sensor is built in.

How do I clear SA 28 SPN 520224 FMI 02 on a Valtra BH 140–210?

First, stop the tractor on flat ground and leave it completely stationary for 5 minutes. If the code remains, repower the guidance controller by turning it off for 30 seconds and then restoring power. If the fault still appears, the guidance controller likely has a hardware failure.

Can the internal roll inertial sensor be repaired separately?

No. The inertial sensors are located inside the guidance controller and are not serviceable individually. If the fault persists, the entire guidance controller must usually be replaced according to the customer’s warranty or replacement plan.

What should I do if the fault disappears after stopping or repowering the tractor?

If the fault clears, it was most likely a false diagnostic. You should report the false diagnostic to AGCO Technical Support, resume normal operation, and continue monitoring the system in case the error returns.

Which Valtra models are affected by this fault code?

This issue applies to Valtra BH Series 140–210 tractors, including BH 140, BH 160, BH 180, and BH 210 models equipped with a guidance controller that uses internal inertial sensors.

What diagnostic tools are recommended for this issue?

AGCO EDT (Electronic Diagnostic Tool) software with a compatible interface such as the AGCO 2×4 CANUSB diagnostic kit is recommended. These tools allow technicians to read and clear fault codes and verify guidance controller operation.