As far as I'm aware, the crusaders did not plan on taking Mecca or Medina in any serious sense.

They were, however, concerned with trying to topple the Fatimid Caliphate in Egypt (before the rise of the Mamluks) - which they attempted several times. One king of Jerusalem in particular - Amalric I - invaded Egypt unsuccessfully five times.

I may be wrong, but I believe there was no serious intention to attempt for the cities of Mecca or Medina, due to the Fatimid Caliphate that could strike quite easily if crusader armies were to leave Palestine and head into the Arabian Peninsula. In addition, those of the First Crusade had a hard enough time avoiding starvation (many times nearly succumbing to thirst or hunger during their march through Anatolia and into Syria) - so a march into the Arabian Peninsula would've likely proved even more disastrous.

Sources: The Crusades Through Arab Eyes by Amin Maalouf (1983) and The Crusades: The Authoritative History of the War for the Holy Land by Thomas Ashbridge (2010)

I'm going to expand your definition of the "Crusades" a bit. Because the Portuguese, specifically under the Estado da India's first governor-general Afonso de Albuquerque most definitely had plans on capturing the Hejaz (where Mecca and Medina were located), as well as Egypt and the Levant, so as to secure their spice trade from India (out of Goa) through the Mediterranean to Portugal.

Now to start off, you might be thinking, well didn't they sail all the way around Africa, to get around having to sail through the Mediterranean? Well the short answer is yes, but it was only a temporary move, as it was far more costly to circumnavigate Africa, than to ship the goods across the Mediterranean. But before 1517 that meant having to capture Mamluk Egypt. After 1517 that meant contending with a brand new power in the Indian Ocean and Red Sea: the Ottoman Empire.

Before the Ottomans had conquered the Red Sea, the Portuguese under Afonso, had already successfully raided all the way up the Red Sea, and were directly threatening Mecca and Medina, even closing down pilgrimage routes that ran across the ocean (granted the vast majority of pilgrims still came across land), as well as trade routes in the all important mixed commodities of spices, which [Mameluke] Egypt had a monopoly on. It was in Afonso's plans that his most Holy majesty, King Manuel I, would complete his crusading duties (a big deal for Portugal, at constant war with the Wattasid dynasty of Morocco*) and conquer Jerusalem. Not only securing a healthy and constant profit from the spice trade, but also completing their crusading objectives.

Needless to say Afonso died too early for his goals to be accomplished, and when the Ottomans did conquer Egypt in 1517, they immediately went on the offensive in the Indian Ocean, by seizing the city-states of Yemen and the hostile interior (some things never change...); and hence closed off the Red Sea to the Portuguese for good**.

Source: Giancarlo Casale: "The Ottoman Age of Exploration"

*Unlike most of the rest of Europe, Portugal was happy to continue its crusading tradition as they had constant contact with Muslims whose land they wanted, and for the religious prestige that it brought.

**Minus one time the Portuguese broke through into the Red Sea, but were routed and eventually completely vanquished, after torching the Ottoman naval arsenal at Suez. (The Red Sea region is very difficult to resupply in as you might imagine).