Yes, there are two meanings:
The door was locked. --> Someone locked the door.
- It can be called a dynamic or eventive passive
The door was locked. --> The door was not unlocked.
- It can be called a false passive or a stative passive
First one is a canonical passive and the second one is a participle used as an adjective. The second one is sometimes called a false passive but if they are considered to be passives, they may be called stative (or static, or resultative) passives, since they represent a state or result. By contrast the canonical passives, representing an action or event, may then be called dynamic or eventive passives.
The ambiguity in such sentences arises because the verb be is used in English both as the passive auxiliary and as the ordinary copular verb for linking to predicate adjectives. When get is used to form the passive, there is no ambiguity: The window got broken cannot have a stative meaning.1
Stative passives (to be + adjective) are less ambiguous when describing emotional states and the adjectives often take a range of prepositions to connect them to the cause of the emotion (instead of agent by-phrase).2 (Related: Prepositional phrase Vs Direct object)
Occasionally, however, even some of these constructions may have a true passive interpretation. In this case, the sentence could have an active counterpart of “Your behavior shocked me.”2
- I was shocked by your behavior.
Sometimes, syntactic ambiguity becomes a bigger problem when transforming some passives into active voice and vice versa. It is a bit beyond this topic but below is an example of a transformation of a more complex structure:
- (passive) Thirteen patients were enrolled and randomly assigned . . .
- (active) We enrolled and randomly assigned thirteen patients . . .
The verb “enroll” can be used with or without a direct object (it can be either transitive or intransitive). That means, in the active version of the sentence above (#2), the reader must resolve which of two potential structures is right — the one in which the writers are the enrollees or the one in which the patients are. Syntactic ambiguity increases cognitive processing time.3
1 Wikipedia / English Passive Voice / Stative and adjectival uses
2 Rochester Institute of Technology / Stative Passive Constuctions Describing Emotional States
3 Pros Write / What happens when passive voice is banned?