IMHO the ship AI would only instruct its robotic maintenance systems to maintain those functions required to ensure minimum efficent sustainment of ship's function per instructions received from the crew; if crew dead, no instructions, therefore sleep mode. If the crew dies, the AI shuts down the systems and waits. Likely would maintian only 0.1% of functional systems for security and communication monitoring. For all intents and purposes it would be a 'dead' thing for those not aware of the technology, so natives would just see is as an incredibly different metal object of no particular use (assuming no internal access).
This is a ship that lands in good repair.
If there is hull breach damage that maintenance robots can't fix, then its another story, but the breach may well be secured by some system that zaps the curious natives with low voltage, requiring nothing more than fencing wire. Low tech counter-measures for low tech threats.