"Boeing’s argument rests on the long service history of the earlier model 737, which has the same wiring. That earlier 737 NG model didn’t have to meet the current wiring-separation standards because they came into force long after that jet was certified. Boeing’s argument rests on the long service history of the earlier model 737, which has the same wiring. That earlier 737 NG model didn’t have to meet the current wiring-separation standards because they came into force long after that jet was certified." (from Seattle Times article)
Not sure who's feeding the reporter that line, but it's not true. It's a single failure that's potentially catastrophic (a hot short to the stab motor wiring). The system safety analysis regulations and policy applicable at the time of the NG application prohibited such a vulnerability. Someone is likely trying to give the impression it is EWIS issue under the relatively new (2007) 14 CFR 25.1707 and 1709 requirements, but it is also non-compliant with the long standing system safety requirements of 25.1309(b), which applied to the NG. Wire separation has always been an element of preventing catastrophic single failures under 25.1309.