Today I removed the ehss module and potentiometer so I could bring them inside where it's warm and dry. The repair manual says the pot output should be 3.2V when the pedal is depressed so I was surprised when I connected my 12V supply and found that output voltage increases when the pedal is pressed. Could the manual be incorrect? No. It's the input voltage that wrong. With a 5V supply, I saw close to 3.2V near the end of the pot lever travel. Pot is fine, I'm sure.
Now all three wires from the pot connect directly to the EHSS module which means one pin (#6) is supplying 5V to the pot. I powered the EHSS module from my bench supply and found that sometimes I could get a 5V reading out of pin 6 but most of the time, it read 0.3V. That's no good. I have a strong suspicion that the 5V regulator in the EHSS module is no good. Of course the thing is potted in resin so I won't be getting it apart without breaking it irreparably. Why is it always the most expensive parts that break?!?!?!?!?!
Here's a picture of my setup for those who care to see it.

Now all three wires from the pot connect directly to the EHSS module which means one pin (#6) is supplying 5V to the pot. I powered the EHSS module from my bench supply and found that sometimes I could get a 5V reading out of pin 6 but most of the time, it read 0.3V. That's no good. I have a strong suspicion that the 5V regulator in the EHSS module is no good. Of course the thing is potted in resin so I won't be getting it apart without breaking it irreparably. Why is it always the most expensive parts that break?!?!?!?!?!
Here's a picture of my setup for those who care to see it.
