What do the SPN and FMI codes mean at Magni?

SPN stands for Suspect Parameter Number and describes which component is affected. FMI is called Failure Mode Identifier and shows how the error occurred – for example, "signal too low" or "short circuit". The combination reveals the exact cause to technicians.

What is the MyMagni system and what is it used for?

MyMagni is Magni's telematics and diagnostic system. It automatically saves all error codes, reports them to the landlord, and helps monitor maintenance and overloads.

How can I read Magni error codes myself?

Error codes appear directly on the display of your Magni RTH or HTH. You can access them via the "Diagnostics" menu. The codes usually consist of an SPN/FMI combination – for example, "SPN 5261 FMI 3". A more in-depth analysis requires an authorized Magni technician.

My Magni won't turn anymore – what does CAN error 5400 mean?

A CAN bus error such as 5400–5402 indicates a communication interruption between the control unit and the rotary actuator. This is often caused by loose connections or a faulty termination in the wiring harness. Shut down the system immediately and call a technician.

My Magni won't start – what does SPN 1015 or SPN 1189 mean?

SPN 1015 indicates a problem with the accelerator pedal signal, and SPN 1189 indicates a missing CAN message from the engine control unit. Both will prevent the engine from starting. Have the battery, connectors, and ECU checked.

How can I tell if my Magni is overloaded?

At 100% load, the system displays a yellow warning; at 110%, the machine partially stops; and at 120%, it stops completely. This is not a malfunction, but a safety function – the telescopic handler will only operate normally again after the load is reduced.

Where can I find a complete list of all Magni error codes?

The complete overview of all SPN/FMI codes is available in the official [document/document/etc.]. Magni Diagnostic Manual RTH REV.01 This document is only accessible to authorized service technicians – you can find a practical selection in our guide on biberger.de.

Magni error code detection & repair (error diagnosis)

What You Need to Know

Magni telescopic handlers feature a modern CAN bus diagnostic system capable of detecting over 170 possible error messages. Most of these are not actual defects, but rather safety functions that protect the machine from damage or overload.Typical causes include damp connectors, faulty pressure sensors, joystick calibration problems, or interrupted CAN signals.Those who understand the meaning of the SPN/FMI codes can better assess risks and avoid downtime.

Only trained technicians are allowed to clear errors or calibrate systems.The operator is obligated to document warning messages and immediately shut down the equipment in case of critical errors. The integrated MyMagni system automatically saves all errors and informs the rental company in real time. This ensures safe operation, protects the machine, and complies with DGUV regulations.

If your Magni telehandler (RTH / HTH series) suddenly displays a warning, it's rarely a total breakdown. Usually, a safety or protective function is being activated. This guide explains the most important error codes, their meaning, and how to react correctly.

Occupational safety notice: Error codes are warning signals , not a clearance to continue working. Even without a visible warning, a visual and functional check according to DGUV regulations must be carried out before every use.

Fundamentals and system structure

Magni telescopic handlers utilize a CAN bus diagnostic system according to J1939-73 . It detects over 170 fault codes. The system is based on the Diagnostic Manual UM Diagnostica RTH REV.01 with defined SPN/FMI combinations and criticality levels.

Control units and diagnostic path

CCU (Central Control Unit): central logic
Engine ECU: Mercedes or Deutz control unit
DM1-CAN-Gateway: collects all messages
Attachment recognition: Potentiometer system
Wireless sensors: remote control and position

Diagnostics via touch display

Automatic error logging
Live data (pressure, sensor values)
System calibration
Emergency release tests

Practical tip: The error codes appear as SPN / FMI . This combination indicates what is defective (SPN) and how it is defective (FMI).

SPN vs. FMI – Explained briefly

Example: SPN 1015 + FMI 1 = "Accelerator pedal voltage too low". SPN 1015 + FMI 3 = "Voltage too high". This allows the technician to pinpoint the fault to the second.

Who is authorized to read and clear error codes?

Operator duties

Read and document the code
Shut down device in case of critical warnings
Send photo or video to landlord
Make an entry in the test log

Authorized technicians

Magni-certified service technicians
Experts according to DGUV 308-009 / TRBS 1203
Authorized rental companies with manufacturer training

Note: Reading errors is not the same as fixing them. Interventions in hydraulics or software should only be carried out by qualified personnel.

Error codes by system area

Hydraulic pressure sensor faults (SPN 5241–5299)

SPN	Error code	Meaning	Caused
5261–5262	MCyl_PHA_TMin/TMax	Rod side outside area	Sensor defective or implausible
5268	MCyl_PHD_MaxDiff	Signal A/B differs	Calibration or leakage
5241–5242	MCyl_PLA_TMin/TMax	Piston side out of range	Sensor failed

Cantilever sensors (SPN 5271–5274)

SPN	Error code	Meaning
5271–5272	R1A/B_TOut	Position signal interrupted
5273	R1D_MaxDiff	Redundant signals differ
5274	R1D_CrossPoint	Potentiometer blocked

Tilt sensors (SPN 5280–5289)

SPN	Error code	Criticality	Consequence
5280–5281	AL_TOut_AmuCA/B	High	Level adjustment disabled
5284–5289	CTilt_X/Y	High	Inclination not measurable

Overload prevention (SPN 5320–5322)

code	Alert level	reaction
5320	100%	Warning, movement is limited
5321	110%	Only relief is possible
5322	120%	Complete shutdown until relief

CAN bus / communication (SPN 5400–5411)

SPN	Error code	Meaning	impact
5400–5402	AL_TOut_MtoL	CAN message missing	Control interrupted → standstill
5410	SlewAux_EncoderFault1	Encoder not recognized	Rotary drive fails

Engine and drive fault (J1939 SPN/FMI)

SPN	FMI	Error code	Meaning	consequence
1015	1	Accelerator PWM	Lacking tension	Machine does not start
1072	3	Decompression Brake	Open circuit	Braking effect reduced
1127	1	Turbo Underboost	Boost pressure too low	Reduced performance
1184	0–3	Turbine Temp High	Overheating	Thermolimit
1233	9	AdBlue Tank Level Low	Tank empty	SCR shutdown imminent
1234	9	SCR Catalyst Efficiency	Catalyst ineffective	Exhaust gas fault, power reduction
5356	5	DPF Regeneration	Regeneration required	Power limited

Most common mistakes in practice

Rank	Mistake	frequency	Stagnation?	Repair time
1	Joystick calibration	35%	No	15–30 min.
2	Pressure sensor differential	25%	Yes	45–120 min.
3	CAN communication	15%	Yes	30–90 min.
4	Tilt sensor timeout	12%	Partially	60 min.
5	Cantilever potentiometer	10%	Yes	90–240 min.

Seasonal sources of error and maintenance instructions

Magni telescopic handlers can be affected by temperature, humidity, and extended periods of inactivity. This overview shows which types of faults occur more frequently depending on the season – and how to avoid them.

season	Typical sources of error	Recommended measures
winter	Battery failures, frozen sensors, viscous hydraulic oil, AdBlue crystallization	Preheat the machine, use heated storage, calibrate sensors, empty or temper the AdBlue tank
spring	Moisture in plugs, corrosion on contacts	Check plug connections, use contact cleaner, test electrical systems
Summer	Overheating due to turbo/DPF, failure of fans or temperature sensors	Clean the cooling system, check the oil level, take regular breaks in high ambient temperatures.
Autumn	Condensation in control housings, false alarms due to temperature fluctuations	Store in a dry place, check seals, monitor the MyMagni error log.

Quick check for error message

Note or photograph the error code (SPN/FMI).
Check criticality (Red = stop immediately)
Move the machine into a safe position
Switch off the engine and inform the rental company.
Do not attempt any repairs yourself.

Conclusion

Magni error codes are not a cause for panic, but rather precise warnings. Interpreting them correctly prevents downtime and damage. This guide provides operators and rental companies with reliable guidance for daily use.

Book Magni training now

About the author

Martin Biberger

Managing Director

Martin is the founder and managing director of BIBERGER Arbeitsbühnen & Forklifts.

He is responsible for thetechnical areaTogether with his team, he is responsible for thetechnical purchasingthe machines thatFurther development of the machine inventoryand the smooth operation of over 1,500 BIBERGER rental devices.

From many years of experience he knows theStrengths and weaknesses of all device classes, the possibleAreas of applicationand thetechnical possibilities– always with a view to theDevelopment of the entire industryand future innovations.

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The subject content on biberger.de are editorially created, reviewed, and continuously updated. The basis is our daily work with aerial platforms, telehandlers, and industrial trucks – in rental, sales, operational planning, and technical support.

Each article draws on real-world experience and is editorially reviewed for clarity, accuracy, and practical relevance according to expert criteria. Technical statements are regularly compared against current industry standards and best practices.

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