Has anyone reset the ECU the old fashioned way. Want to reset the ECU memory.

[19EdgeSTeve]

I have had several tunes, i think the ECU has learned some bad behavior.  Can we still do the battery trick and drain the ecus memory?

[todd92]

I'm not sure that ever actually did anything.

[omar302]

As far as I know, yes, disconnecting the battery for a few minutes does reset some learned values in the ECU (PCM). It is still stated in the owners manual for the 2019 ST.

 

Quote

 

Because your vehicle’s engine is electronically-controlled by a computer, some engine control settings are maintained by power from the low voltage battery. Some engine computer settings, like the idle trim and fuel trim strategy, optimize the driveability and performance of the engine. Some other computer settings, like the clock and radio station presets, are also maintained in memory by power from the low voltage battery. When a technician disconnects and connects the low voltage battery, these settings are erased. Complete the following procedure in order to restore the settings:

1. With the vehicle at a complete stop, set the parking brake.

1. Shift the transmission into park (P).

1. Switch off all accessories.

1. Fully press the brake pedal and start the vehicle.

1. Run the engine until it reaches normal operating temperature. While the engine is warming up, complete the following: Reset the clock.   See   Audio System.  Reset the power windows bounce-back feature.
     See   Windows and Mirrors.  Reset the radio station presets.
     See   Audio System. 

1. Allow the engine to idle for at least one minute.If the engine turns off, press the accelerator pedal to start the engine.

1. While the engine is running, press the brake pedal and shift into neutral (N).

1. Allow the engine to run for at least one minute by pressing on the accelerator pedal.

1. Drive the vehicle at least 12 mi (20 km) to completely relearn the idle and fuel trim strategy.

Note:   If you do not allow the engine to relearn the idle and fuel trim strategy, the idle quality of your vehicle may be adversely affected until the engine computer eventually relearns the idle trim and fuel trim strategy.

 Make sure that you dispose of old batteries in an environmentally friendly way. Seek advice from your local authority about recycling old batteries.