Machine is showing error 30 how do I fix that

Precor Error 30, 31, 32 and 33, Communications Error Probable Cause 1. Bad interconnect cable between upper PCA and lower PCA.
2. Interconnect cable is mistakenly plugged into the CSAFE connector at the upper PCA.
3. Elliptical 5.17 equipped with old software version 1.01 in upper and lower PCA.
4. Upper and lower PCAs have mismatched software.
5. Another component plugged onto the PCA is overloading the +5VDC power supply.
6. Bad lower PCA.
7. Bad upper PCA.
Corrective Action

1. Test unit with a know good interconnect cable or test the interconnect cable for continuity. Replace interconnect cable if necessary.
2. Disconnect the interconnect cable from the CSAFE connector and attach to the proper position on the upper PCA.3.
3. Replace the upper and lower software of the 5.17 elliptical with the most current versions.4.
4. If one of the PCAs is found to have software version 1.01, replace it with the most current software version.
5. Disconnect all components from the upper and lower PCA leaving the data cable connecting between the upper and lower PCAs and the AC power going to the lower PCA. If the unit shows any error other than the error 3x, reconnect components one at a time. Reset power between each newly connected component until the error 3x reappears. Whichever component was last connected when the error 3x reappears, is the cause for the error. Replace the faulty component.
6. Test unit with a known good lower PCA. Replace the lower PCA if necessary.
7. Test unit with a known good upper PCA. Replace the upper PCA if necessary.