There are several ways to tune or re-calibrate an engine control unit (ECU). The first ECUs developed were fitted with so called (E)PROMs (Erasable Programmable Read Only Memory). A chip that has data with all the maps, flags and code to read the sensors and activate the actuators of the engine control unit. To rewrite the code and maps in such ECUs the EPROM has to be removed and read with a chip or device programmer. Nowadays we don’t have to do such work.

In most cases the laptop can be connected to the car to read and write the calibration. An overview of available “tuning ways” which we support can be seen below:

• (EE)PROM removing, reading, writing (Electronical Erasable Programmable Read Only Memory) (~1980 – current)
  The content of a chip is read by removing it and placed in a device/chip programmer. After re-writing of the data the chip is erased by UV light or by the device programmer and written to the (EE)PROM. Some chips are PROM, which simply means they can be written once (OTP One Time Programmable). To write the new calibration a new chip has to be used.

  
• Flashing(1996 – current)
  Flashing is one of the easiest ways to retrieve and write the content of an ECU. The data is retrieved in most cases by the diagnostic socket or so called OBD port of the vehicle. The interface that is connected to the diagnostic socket is communicating with the ECU to read or write the calibration. Flashing comes from Flash chips that are a bit similar than EEPROMs. Were an EEPROM has to be completely erased before writing, Flash chips can be erased and be written in sectors.

  

• Flashing ECUs with tuning protection [TriCore](~2007 – current)
  Infineon TriCore processor Technician busy retrieving the content of an ECU

  Manufacturers have developed protection ways to avoid re-calibration of the ECU. So called tuning protection. This kind of protection disables writing of the ECU by the diagnostic socket/OBD port. Karreman Engineering is able to remove the protection from the ECU and make the ECU “tunable” by the diagnostic socket. The only downside is that we have to remove the ECU from the car and access the microprocessor by some kind of BDM (see below) method to disable the protection. This involves some extra time depended on how the ECU casing is secured. This extra time has been taken into account in the selling price. We have advanced tools to open the ECU case and put it back to original.

  
• BDM (Background Debugging Mode) (~2000 – current)
  A connection to the ECU circuit board is made.

  If flashing is not possible, if the complete content of an ECU needs to be retrieved for back-up reasons or after a flash failure BDM method can be used there were applicable. With BDM you “open” the ECU case and read/write the data by directly communicating with the microprocessor instead by the communicating with the (CAN)-BUS systems like flashing.

  
• Stand alone or self programmable ECU
  Stand alone or self programmable ECUs are populair in racing cars. The ECU can be fully programmed by the user with delivered software from the manufacturer of the ECU. In most cases this is the most expensive way to tune a car. The ECU needs to be programmed to the engine and a wiring harness needs to be made. The price for these systems can be as low as paying for a tuning for your car to the cost of a second hand car. Click here for more information on stand alone ECUs

  
• Tuning Box
  A tuning box is placed between sensor(s) and/or actuator(s) of the ECU. The tuning box activates the actuators (example: fuel injectors, turbocharger PWM valves) by the programmed values set in the device. Sensors are read and the supposed value is returned back to the ECU so it won’t go in to limp mode. With a tuning box you are actually fooling the ECU. Tuning boxes can be used in nowadays vehicles were regular (flashing) solutions are not developed or available.

  

  Why not use a stand alone? Nowadays ECUs control more than just only the engine. The (automatic) gearbox needs signal and messages from the engine control unit to operate. Even the instrument cluster in the car needs to communicate with the engine control unit to tell the driver the engine speed the engine is running. Besides the communication between modules new engines have sophisticated control systems that stand alone ECUs can not control. If they can, the cost for these ECUs are extensive that customers would avoid.

  We have delivered and equipped a few cars with so called tuning boxes. Vehicles that are not able to be re-calibrated by its own ECU due to high security settings in the ECU. Customers can still enjoy a power increase that would be equal than with re-calibrating the stock ECU. An example is a BMW 528i F10 from 2011. Stock power is 245bhp (180kW) and 350Nm of torque. With a tuning box the power and torque can be optimized near 275-285 bhp (202-210kW) and 400Nm of torque. Even more is possible with hardware (exhaust, engine) modifications.