Bylund Automotive Support

Hi Christian,

Background: Have dual Bylund system set up with all hardware purchased from you---Arduino UNO, Shield, 4.9 Bosch sensors.

Data is displaying on a .96" OLED. There was an issue with the icons cutting off on the far right and the cut offs showing on the display's far left. This was found to be a common glitch. Adjusting the icon and text positions in the sketch solved this. Displayed content looks good now.

Problem I need your advice with is:

1. Display freezes soon after startup. Sometimes the data restarts to flow. Sometimes the display returns to the "Bylund" logo and the heater blinks (even though it would seem the heater should already be at operating temp) and the data once again flows on the display. Then again... another freeze.

Appreciate your input on this.

Karl ~~~

Further testing...

Freezing being a possible memory issue, the display font in Bylund's sketch was reduced from 24pt to 12pt. "Used space" dropped from 80% to 70%. This resulted in a distinct increase in display stability but it's still not operating consistently. Flowing data was sufficient to drive the car under various loads to see what would display. AFR fluctuated 0.01 decimal point and Lambda never changed from .99 no matter what load the engine was put under. This data is inaccurate as the values should significantly change under various engine loads.

So while data display stability has improved, the data displayed is inaccurate.

Different, new OLEDs have been tested with the same results so the issue being in the display is already ruled out.

Three more tests to do:

1. Use the second Arduino/Bylund shield in place of the first one --- perhaps first boards are faulty.
2. Replace the installed Bosch 4.9 sensor with a second --- perhaps the first Bosch sensor is faulty.
3. Remove the snubber attached to the relay that switches 12v power ON/OFF to serve the Bylund shield. (Arduino has a separate power circuit with a step-down that reduces 12v to 5v.)

Final tests:

1. Use the second Arduino/Bylund shield in place of the first one --- perhaps first boards are faulty.
Result: With the 24pt original text size in this sketch, display froze within 20 seconds of start up.

2. Replace the installed Bosch 4.9 sensor with a second --- perhaps the first Bosch sensor is faulty.
Result: No data on screen, only logo. Disconnected and reconnected junction to sensor cable and no change.

3. Remove the snubber attached to the relay that switches 12v power ON/OFF to serve the Bylund shield. (Arduino has a separate power circuit with a step-down that reduces 12v to 5v.)
Result: Same no data on screen, only logo.

Indication is the second 4.9 sensor is no good. And this is the first time it has been installed.

Conclusion:waste of time & money.

Hello Karl,

Let's see if we can figure this out, we usually do.

Larisabex wrote: ↑

12 Sep 2024 07:36

Remove the snubber attached to the relay that switches 12v power ON/OFF to serve the Bylund shield. (Arduino has a separate power circuit with a step-down that reduces 12v to 5v.)

Could you please clarify how you are powering the devices? - A picture would be very helpful on how power is connected to the Arduino and shield.

Thank you.