Normally-open type B:
Check for continuity between the terminals.
- There should be continuity between the No. 1 and No. 3 terminals when power and ground are connected to the No. 2 and No. 4 terminals.
- There should be no continuity between the No. 1 and No. 3 terminals when power is disconnected.

Rear window defogger relay

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Blower motor relay
type 1:

type 2:

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