[glitchcrab]

You're correct that the dongle only facilitates the connection, but you don't need dealer software. I have an ODB dongle and a £20 (I think) app on my phone which lets me change a _ton_ of settings on my BMW which aren't available in any in-car menus.

[psd1]

What app?

[glitchcrab]

Bimmercode lets you do coding (it's very powerful and you can easily mess up your car so you have to be very careful with it), and Bimmerlink lets you read fault codes etc.

[psd1]

Does it label the fields, or are you following forum instructions to write 0x01 to module 76 channel 004?

[glitchcrab]

Safer settings are exposed with decent labels, but you can also use the advanced mode which is much more low-level, akin to what you described.

[psd1]

Thanks, i learned something new. I think we're both right by degree. That app is more functional than anything I've found, but there comes a point where you need someone to tell you the modules and fields or you risk bricking your car.

[glitchcrab]

Oh for sure, but you can do a lot of things without ever touching the advanced coding section. It's definitely worth being cautious though - as you say you can definitely brick your car with it if you're just YOLOing your way through it. It does back up the module configuration prior to writing the update though so you do have a safety net.