Boeing agrees with the PSEU replacement and would recommend performing the PSEU LRU Replacement test per AMM TASK 32-09-10-710-801. Following the replacement test we would expect the 32-64001 message to be cleared and no further messages.
However, if Hainan Airlines Holding (HNA) is not able to complete the replacement of the wing position light lens before the airplane is dispatched and this would cause a delay, then Boeing suggests the following for this particular case:
a) Apply at least 2 layers of high-speed tape onto the entire cover with 50% overlap.
b) Trim the speed tape as required to obtain a smooth surface.
c) The light must be deactivated by opening the relevant circuit breaker and limited to daylight operation only.
d) Apply MEL 33-11 for daylight operations. The airplane must operate during daylight hours (sunrise to sunset).
e) Inspect the temporary repair prior to each flight to ensure that there is no further damage to the lens/aluminum speed tape and that there is no moisture ingress into the lens.
f) Boeing recommends replacing with a new lens at the earliest opportunity when the part is available or before 5 Flight Cycles. Continued use of the speed tape could allow water ingression and damage to the light assembly.