07-09 MERCEDES S550 ECU ECM ENGINE COMPUTER A 273 153 12 91 0261209379 TESTED

Please match the following 0 261 209 379. We recommend matching the following but believe your MB shop can update this: A 273 153 12 91

• You must match your part number exactly as seen above. If any numbers are off compared to your original it will not work properly.
• Ecu will require programming or coding to your vehicle or vehicle's security system and is not plug and play. You will need to take this to your local BMW/Mercedes/VW "IMPORT SHOP" for programming. Your dealer will more than likely refuse to perform the programming or say it can't be done.
• Ecu will fit 2007-2009 S550 models with an exact part number match. This may fit other vehicles with the same part numbers, programming is a must!

ECU has been tested with our state of the art vehicle simulator which tests over 25 circuits of the ECU! Some of those are listed below:

• Reference Voltage Good!
• ECU powered up and has communication!
• ECU fuel pump/main relay test good!
• The problem areas on the PCB that cause a no crank with the cooling fan running have been tested good or repaired.
• ECU injectors/coils circuits test good

• Disconnect the negative terminal of the battery. Make sure the battery connector is not touching the battery post.
• Disconnect and remove the module to be replaced.
• Install and connect the replacement module.
• Connect the negative terminal of the battery.
• Ecu will now need programming or coding to your vehicle.

• Pins perfect, none are broken or bent
• Mounting points are perfect!

This ECM comes with a 90 day warranty from the date of purchase. Please keep a copy of your purchase record which we will send with your item.

If you would like to send your ecu back for a $30 core refund please let us know during checkout and we will include a prepaid return label with your purchase. Once the core returns we will issue your partial refund promptly. It's that simple. This is optional and you are not obligated to participate.