It is most likely the multipurpose relay. All these types of relays sit behind the fuse box. Unscrew the (6?) screws and it hides behind the plastic cover.

You can try just giving it a firm tap with your fist to see if anything happens -- Sometimes this will temporarily fix problems like this. If you notice any difference, you can pull it apart and resolder any bad joints. Many members have fixed problems by doing this instead of buying the the part.

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