Trailing 1-0 after the first leg in which the Germans had to play most of the game with 10 men after Franck Ribery's sending off, Lyon striker Lisandro Lopez and coach Claude Puel said the Ligue 1 side need to up the ante.
"The team must change its attitude, its mentality. We played too defensively. We must have a more positive mind-set. We need to change tactics if we are to progress," Lisandro told reporters.
The Argentine said Lyon should be inspired by their performance at the Bernabeu in the first knockout round when a 1-1 draw gave them the edge against Real Madrid after a 1-0 win in the first leg.
"We've made it once, we can do it again. That day, we all wanted to go through."
Puel said Lyon were likely to be a better team now that they have their backs against the wall.
"I prefer this (kind of situation) because we play better when we have to go and get a result," he said.
DEFENSIVE WOES
Puel, however, has some defensive woes before the clash at their Stade Gerland, with centre-back Cris doubtful with hip and knee pains, Mathieu Bodmer ruled out injured and Jeremy Toulalan suspended after picking up a red card in Munich.
Centre-back Jean-Alain Boumsong has resumed training following a calf injury and should at least be in the squad.
Following their scrappy 1-1 league draw against Borussia Moenchengladbach on Saturday, Bayern must up their tempo and they will have to do that without playmaker Ribery, suspended following his red card in the first leg.
Ribery will be joined on the sidelines by Croat Danijel Pranjic, who is also suspended.
As Bayern chase an unprecedented treble for a German team with domestic honours also in their sights, they are also concerned about a potential weakness in their central defence.
Martin Demichelis and Daniel van Buyten picked up injuries in the game against Gladbach and are racing against the clock to be fit for the match.
"I could not step on my leg after the hit," Van Buyten said after taking a knock on the thigh and limping off. "It is even worse now and I do not know if I will have enough time to recover by Tuesday."
Demichelis was taken off at half time with a thigh muscle injury.
But Bayern sports director Christian Nerlinger sounded confident both would be fit in time, saying: "As things stand now I assume both will be available for the match against Lyon."
Captain Mark van Bommel will add steel to the midfield with the Dutchman returning to Champions League action after sitting out a suspension in the first leg.
Probable teams:
Olympique Lyon: 1-Hugo Lloris; 13-Anthony Reveillere, 4-Jean-Alain Boumsong, 3-Cris (or 41-Maxime Gonalons), 20-Aly Cissokho; 41-Maxime Gonalons (or 17-Jean Makoun), 6-Kim Kallstrom; 10-Ederson, 8-Miralem Pjanic, 19-Cesar Delgado; 9-Lisandro Lopez.
Bayern Munich:
