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Rotary switches for calibration changes, type question

PostPosted: Tue Nov 08, 2011 7:53 am
by Chris Wilson
I want to make some 10 position rotary switches for calibration purposes, things like dash mounted boost or traction control. I will have a 220 ohm resistor across each pair of pins around the switch, and one each in series in the 0V and 5V wires. Does it matter if they are break before make, or will the ecu see a voltage drop to zero as a glitch, and I should use make before break types? The reason I ask is the switch I made and am using at the moment for boost control threw the odd diagnostic error at the weekend, until I set Diagnostic low to a minus figure. I am guessing it may have been due to the ecu seeing momentary zero volt figures when I changed switch positions? The error only showed at such times. I have a feeling I could maybe sort this with a high filter setting, but would rather ask first. Would a high filter figure effectively introduce a delay before the ecu read the voltage from the switch? Thanks.