it should be EV100
prob more like 10 years old

let me start of like this
NEVER STEAM CLEAN OR PRESSURE WASH ELECTRONIC MACHINES
or anything that has technology past the 60s for that matter

code -71 is no input from green wire to regen current sensor

there is something called a regen assy
next to the card there is a large heatsink with large rectifiers and a large capacitor (rectifier = large pigtail diode)
the regen assy is another smaller heatsink with 1 large rectifier and a current sensor
the sensor is a copper bar with 2 wires soldered to it (a green and yellow)
the wires are twisted together (twisted pair, like a telephone or ethernet wire pair)
make sure the green wire didnt come loose off the sensor

on the control card
there are 2 small plugs and 2 large plugs and a terminal board
in the smaller plug closest to the outside edge of the card you will find the other end of the green wire
this plug is called the PA plug
the green wire is in pin 5

sometimes if this plug gets dirty or oxidized (from the pressure washer) you can lose the connection or degrade it to the point the card cant read it
simply unplug the PA plug and plug it back in
this cleans the pins by scraping them
repeat this for the other 3 plugs as im sure youre washing would have had similar results on other pins
you should also use a good non-conductive electronic parts cleaner in the plug side
and pack them with a dielectric grease to prevent this from happening under normal circumstances (pressure washing would have blown this stuff away even if it was present before hand, after 1999 it was standard to pack the plugs at the factory)

again do not pressure wash the machines
even newer IC machine have computers that do have weather packed connections
but a pressure washer will get right past that without much effort

if you want take a picture of the control box and send it to my email (in my profile) i can label the pic of what you need to check and send some literature on what GE recommends to use to clean and pack the plugs