Learn French: L'équipe ne fait plus appel à eux. - The team no longer calls upon them.

The expression faire appel à (to call upon or appeal to) belongs to a specific group of verbs and phrases that do not allow you to use the indirect object pronouns lui or leur for people. Instead, you must keep the preposition à after the verb and follow it with a stressed pronoun like eux.

Can faire appel à be used for non-human things, like a memory or a rule?

Yes, but the pronoun changes! When calling upon something non-human, you use the pronoun y placed before the verb instead of keeping à after the verb. For example, to say 'The team no longer calls upon it,' you would say L'équipe n'y fait plus appel.

If the sentence were in the passé composé, where would à eux go?

It stays exactly where it is, at the end of the sentence. Because it is a stressed pronoun attached to a preposition, it does not move before the verb. The passé composé would be L'équipe n'a plus fait appel à eux, with the negation ne ... plus wrapping around the helper verb a.

Does faire appel à eux mean the team is no longer physically calling them on the phone?

No, for a simple phone call you would use appeler or téléphoner à. Faire appel à means to 'call upon' or 'appeal to' someone for their services, help, or expertise.