ECU ‘TEC-GT’ (Engine Control Unit)

The TEC-GT is a newer generation ECU from Electromotive than the TEC-3.

The hardware platform, with 4 CPUs, should be more powerful and handle more I/O functions simultaneously.
The unit contains all the same engine sensor systems and DFU controls as the TEC-3, but in addition it now has 9 programmable I/O lines. The O2 sensor input now takes both a narrow and a wide band sensor.
The PC software is totally new, called TEC-4, and the ECU firmware could be uploaded with every new software release.

New PC software will be compatible with older TEC-GT firmware, and the ECU now  includes a boot load system in case an firmware upload fails.

In that case, the unit now contains a master rest switch, which should be used and perform a boot-load that solves the deadlock situation.


I replaced the TEC-3 with TEC-GT in 2008.

Mechanically the TEC-GT is a little longer and not as wide. I had the TEC-3 mounted on a 6 mm AL adaptor plate. This plate was modified to mount the TEC-GT instead. A 12 pole terminal row was also mounted on the adaptor plate for easy access to all the main sensor signals. The previous tuning work had shown that this would be nice to have.With the TEC-GT, for whatever illogical reasons, all the analog input signals are inverted compared to the TEC-3. This means fuel, ignition, boost pressure… manually controls are working opposite. I hope Electromotive will correct these functions in a later firmware release.

The TEC-GT is operating over a very wide dc input range. It works reliably from 5.5 volt dc and only draws 180mA.

NOTE: Any use of the analog output should NOT be pulled-up to a non switched 12 volt (example a relay), as this will backward power the unit ‘ON’ through the output pin. Then it’s not possible to switch the TEC off.