Or if it shifts straight from 1st to 3rd and has no 4th, you probably snapped the 2nd gear band or it's anchor pin. Splitting hairs, the 4l60 wasn't electronic, that was just the new name for the th700r4 when they decided to standardize/patternize the naming convention. The 4l60e is the electronic valve body variant.If you have a vehicle with a 4L60 automatic transmission (a common GM trans in trucks and SUVs since 1993) that shifts from 1st to 2nd and when it should shift to third the engine starts revving up, it's not an electronic problem. It means that the 3-4 clutch has failed.
Speaking of the naming convention:
4 - forward gears
L - longitudinally mounted
60 - Newton meters torque capacity (x10)
e - Electronic shift