A little back ground.

Audi S3 with narrow band APY ecu.

Presently upgrading to Wideband Loom and ECU ( S3 BAM )to allow for better tunning on the Hybrid

If I were to run a switch circuit from Pin 24 to the ECU ground via the cars cockpit, to allow me to put the ecu into bootmode when out and about with out the need to remove the ecu and jumper the pins, any reason why this might not work?

Would it just be a case of closing the switch to make the circuit, turning on the ignition, opening the switch and the ecu will then be in bootmode? I was just worried about the permanent + feed into the ecu and whether this might stop bootmode being activated.

Yes, i did this with two ecus

one has a pushbutton and a hole drilled in the ecu enclosure (hard to get to, need a screwdriver to hit the button)

the other has a momentary switch mounted to the back of the enclosure using very short wires.



both are completely stable.

i dont know that i would trust a LONG wire into the cabin. I'd probably make some sort of FET circuit for that.