- Garden
- Robot lawnmower
1200
STIHL 1200 on iMOW robot mower: mowing motor will not start
Risk level
High
Professional inspection is recommended.
Urgency
Medium
Quick answer
The iMOW shows 1200 after five failed attempts to start the mowing motor. STIHL points to dirt between the carrier plate and the housing or to overload. Disable the mower, wear gloves, clean the blade and mowing deck and set a higher cutting height.
Safety first
Stop and check this first
- STIHL warns that a worn blade may break off and cause serious injuries: disable the mower, wear gloves and never resharpen the blade, replace it.
- Do not clean the mower with a hose or pressure washer: STIHL warns that water on motor parts, seals or electrical components can cause expensive damage.
Safe checks you can perform
- Disable the mower and set it in the cleaning position
- Clean the blade, mowing deck and carrier plate
- Inspect the blade and raise the cutting height
Leave these tasks to a qualified professional
- Do not attempt this professional task: Mowing motor diagnosis by a STIHL specialist dealer
- Do not attempt this professional task: Blade, carrier plate or nut replacement at the workshop
What a technician must be able to justify
Technician visit
These are the steps they must carry out and show you. Tick them as they work: if steps are skipped, do not accept a part swap.
These are not instructions for opening or handling the equipment yourself. They are the checks that should support a technical conclusion.
Mowing motor diagnosis by a STIHL specialist dealer
What they doIf 1200 persists after cleaning, STIHL asks you to contact a specialist dealer, who can test the mowing motor and its connection.
They must show youthe mowing motor start test and the messages stored in the mower.
In writingthe cause found, the parts replaced and the repair warranty.
Blade, carrier plate or nut replacement at the workshop
What they doIf the blade, carrier plate or fastening nut is broken or worn, the dealer can fit genuine STIHL spare parts.
They must show youthe parts removed and the STIHL spare part numbers of the new ones.
In writingthe part numbers fitted, the price and confirmation that the blade is securely seated.
Before accepting a part or repair
Nothing has been shown yet. Do not accept a part swap based on the code alone.
Follow these steps
Note: Follow the documented order. An error code identifies the affected system, but it does not prove by itself which part has failed.
Disable the mower and set it in the cleaning position
- Who:
- you, before putting your hands anywhere near the blade.
- How:
- press and hold STOP to activate the disabling device and let the mower cool for about 5 minutes, as STIHL asks before maintenance. Put on protective gloves, tilt the mower onto its left side and lean it securely against a stable wall.
- Result that matters:
- the mower disabled, cool and safely propped with its underside reachable.
- If it will not sit steadily against the wall:
- stop and find a better support before touching the blade.
- If it is disabled and well supported:
- go on to clean the mowing deck.
- Evidence to keep:
- a photo of the 1200 message on the display before disabling the mower.
Evidence: STIHL iMOW RMI 632 and RMI 632.1 Instruction manual (0478 131 8354 D)
Clean the blade, mowing deck and carrier plate
- Who:
- you, with protective gloves on and the disabling device active.
- How:
- scrape out clipping deposits from the housing and mowing deck with a stick, and clean the blade with a brush or cloth. Where your manual describes it, remove the carrier plate with the puller and clean the blade shaft and its mounting. Never use pressurised water.
- Result that matters:
- a carrier plate that turns without rubbing against the housing.
- If there was a layer of packed grass:
- after cleaning, unlock the mower and confirm the message.
- If everything was clean and the plate turns freely:
- look at the cutting height and the state of the ground.
- Evidence to keep:
- photos of the underside before and after cleaning.
Evidence: STIHL iMOW RMI 632 and RMI 632.1 Instruction manual (0478 131 8354 D)
Inspect the blade and raise the cutting height
- Who:
- you, with the mower still disabled and gloves on.
- How:
- look for notches, cracks or wear on the blade; STIHL says to replace it and never resharpen it. Then raise the cutting height to ease the load on the motor if the grass is long, and level out holes or dips in the mowing area.
- Result that matters:
- a blade in good condition and a height that does not strain the mowing motor.
- If the blade is damaged or worn:
- replace it with a genuine one or have the dealer do it.
- If the blade is fine and 1200 comes back with the height raised:
- stop using the mower and take it to the dealer.
- Evidence to keep:
- the cutting height you set and a photo of the blade.
Evidence: STIHL iMOW RMI 632 and RMI 632.1 Instruction manual (0478 131 8354 D)
Still not solved
If the error persists, stop here. See what the technician must do and show you.
Where this code applies
A code is meaningful only inside the right product and version context.
Primary scope
- System
- Garden
- Brand
- STIHL
- Product type
- Robot lawnmower
Known code variants
- 1200 Avería motor corte
- 1200 Mowing motor fault
- arranque del motor de corte imposible tras 5 intentos
- iMOW 1200
- iMOW blade motor will not start
- iMOW motor de corte no arranca
- mowing motor start not possible after 5 attempts
- RMI 632 error 1200
- STIHL 1200
What it means
In the messages chapter of the RMI 632 and RMI 632.1 instruction manual (PDF page 82), message 1200 "Mowing motor fault" means the mowing motor could not be started after 5 attempts. STIHL lists three possible causes: dirt between the carrier plate and the mowing deck housing, the mowing motor cannot be switched on, or the mowing motor is overloaded. It suggests cleaning the blade, mowing deck and carrier plate, setting a higher cutting height and levelling the ground. Seeing this code is not enough to call the mowing motor faulty.
Warnings and stop conditions
- Highsource verified
STIHL warns that a worn blade may break off and cause serious injuries: disable the mower, wear gloves and never resharpen the blade, replace it.
Evidence: STIHL iMOW RMI 632 and RMI 632.1 Instruction manual (0478 131 8354 D)
- Mediumsource verified
Do not clean the mower with a hose or pressure washer: STIHL warns that water on motor parts, seals or electrical components can cause expensive damage.
Evidence: STIHL iMOW RMI 632 and RMI 632.1 Instruction manual (0478 131 8354 D)
Symptoms and causes
Probable causes · in order
- Dirt between carrier plate and housingCommon
STIHL explains that deposits between the carrier plate and the mowing deck housing create friction and raise power consumption, especially in wet weather.
Evidence: STIHL iMOW RMI 632 and RMI 632.1 Instruction manual (0478 131 8354 D)
- Overload from long grass or uneven groundPossible
The manual suggests setting a higher cutting height and levelling out holes and dips when the mowing motor is overloaded.
Evidence: STIHL iMOW RMI 632 and RMI 632.1 Instruction manual (0478 131 8354 D)
- The mowing motor cannot be switched onLess common
This is one of the causes STIHL lists; if cleaning does not help, a persistent message should be checked by a specialist dealer.
Evidence: STIHL iMOW RMI 632 and RMI 632.1 Instruction manual (0478 131 8354 D)
Virtual technician
Does 1200 still appear after these checks?
Answer a few questions to narrow down the likely cause and the safest next action. Guidance only - it never replaces a professional.
Sources and technical references
- 1
STIHL iMOW RMI 632 and RMI 632.1 Instruction manual (0478 131 8354 D)
STIHL · 2021 · manual
- 2
STIHL iMOW RMI 632 y RMI 632.1 Manual de instrucciones (0478 131 9254 D)
STIHL · 2022 · manual
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