Reverse polarity on a DME harness taught me to trust the manual over my memory

Been doing this since 2015, mostly on corporate jets in the DFW area. Last month I was swapping a DME in a Hawker and hooked the tray wiring by feel, same way I'd done it a hundred times. Fired it up, got nothing but a blank screen and a burned smell from the back of the unit. Turns out the previous shop had rewired the pins 2 and 6 to a nonstandard config. My muscle memory was dead wrong. The manual sketch on page 3 of the IPC showed the actual factory layout. I had to eat the cost of a new card and about 4 hours of labor. After that, I started pulling up the pinout diagram on my tablet before every install, even the ones I know cold. It's slower but it's saved me twice since. Anyone else get burned by trusting their habit over the drawings?

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