Repairing the FRM Module (Footwell Module) with a Programmer – Step-by-step Guide
Reliable solution for BMW & Mini Cooper vehicles
Repairing an FRM module—commonly found in BMW and Mini Cooper models—requires technical expertise and precision. At ABS-Stuurapparaten in Heemskerk, we offer diagnostics and overhaul of FRM modules. Below, you'll find a detailed manual for those who want to get started with an internal memory programming device themselves.
🔧 What is an FRM module?
The FRM (Footwell Module) controls several electrical functions, including:
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Indoor and outdoor lighting
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Direction indicators
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Electric windows
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Mirrors
A defective FRM module often occurs after a dead battery and can lead to communication problems or loss of these functions.
⚠️ Please note : This procedure requires experience with electronics.
✅ Always make a backup of EEPROM & Flash
✅ Use a stable 12V power supply (minimum 3A)
🛠 Supplies
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Internal memory programming device
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Associated software
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ISP cable or adapter (e.g. for MC9S12XEQ384 – mask: 0L15Y)
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Power supply 12V / min. 3A
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(Optional) Soldering equipment and pinout adapter
🔄 Step-by-step plan for FRM3 repair
1. Disassemble the module
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Disconnect the battery
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Locate the FRM (usually near the driver's footwell)
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Remove the module and open the case
2. Identify the microcontroller
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FRM3 usually uses MC9S12XEQ384 (mask: 0L15Y)
3. Connect to the programmer
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Connect to the PC and start the software
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Manually select the correct type
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Connect VDD, GND, BKGD, RESET according to pinout
4. Read data
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Make a backup via 'Read EEPROM' and 'Read FLASH'
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Do you only see FF? Then the memory is probably corrupted.
5. Restore EEPROM
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Load an original or repaired dump in
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Or use the 'EEPROM Repair' function (if available)
6. Write data back
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Use 'Write EEPROM' (and Flash if necessary)
7. Inspection and installation
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Check if the EEPROM has been written correctly
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Remove the programmer and replace the module
🚗 In-vehicle adaptation
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Reconnect the battery
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Use a diagnostic interface (INPA, ISTA, Tool32, Autel, Launch) to:
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Clear error codes
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Test the functionality of windows, mirrors and lighting
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💡 Tips & Points of Attention
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Always ensure a stable power supply
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Do not use 'auto detect' for defective modules
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No valid backup? Search online for a dump with the same part number.
Have your FRM module repaired by professionals?
At ABS-Stuurapparaten in Heemskerk, we offer professional diagnostics and regeneration of FRM modules with a 2-year warranty . Simply send us your part or use our pickup service.
Questions? Contact us via the contact form ; our team is happy to help!
Common FRM error codes:
- A3B4 Incorrect message (lighting status), transmitter: FRM
- A3C1 Incorrect message (lighting status), sender: FRM
- A559 Instrument panel power turned off
- 9CBB / 9CBC / 9BCC : Short circuit faults
- 497F Error in reverse gear message
- E72B / E72C Window Errors
- 00A3B4 message error lighting state receiver instrument panel, transmitter foot
- 00A3C1 message error footwell module receiver instrument panel, transmitter foot
- 00E1E3 message reverse gear faulty receiver CIC transmitter FRM
- S0114 no communication with control unit possible
Compatible vehicles with FRM:
