In the pod bay, Dave is examining the retrieved AE-35 unit with an electronic circuit tester. Frank and Hal watch. Dave appears to be completely absorbed in his examination. Frank is hunched over and appears to be watching Dave but he noticeably moves his eyes and stares at Hal. The testing goes on and all we hear is the sound of the testing equipment against the hum that is always present on board the Discovery. There is a noticeable sigh and then Dave finally breaks the silence with "Well Hal, I'm damned if I can find anything wrong with it." Hal responds "Yes...It's puzzling...I don't think I've seen anything quite like this before." Hal then suggests putting the unit back to let it fail and diagnose it after that. He then mentions that they could afford to be out of communication for the short while.
In the centrifuge, Frank and Dave are watching a transmission from Mission Control. They agree with Hal's suggestion of putting the original AE-35 unit back in place. Then a bombshell is dropped. The Mission Control man informs Frank and Dave that Hal may have been in error predicting the fault. This assertion is backed up by the findings of a twin 9000 series computer back on Earth.
When the transmission ends, there is a brief but awkward silence that is broken by Hal. "I hope the two of you are not concerned about this?" Dave responds by questioning Hal's explanation for the discrepancy between the two 9000 series computers. Hal responds with it being "human error". Frank then takes over the questioning. He asks for assurance from Hal that there has never been an error in the 9000 series. Hal reminds him that the 9000 series has a perfect operational record. Frank, obviously not satisfied, asks if there has ever been any incidence of the most insignificant computer error. An obviously annoyed Hal responds "None, whatsoever Frank. Quite honestly, I wouldn't worry myself about that." Was this a veiled threat? Frank's expression indicates he took it that way. Dave interjects, knowing that Frank challenging Hal could not possibly solve anything. He assures Hal that everything is fine. He also asks Frank if he can check out a problem he is having with one of the pods.
It is obvious that Dave wants to talk to Frank alone without Hal being able to listen. The two men get into a pod, rotate it, then turn off all the audio switches. When they are satisfied that Hal cannot hear them, they proceed to discuss their situation. Dave seems ambivalent but Frank makes his point clear. He is very uncomfortable about Hal. So uncomfortable in fact that he completely dismisses Dave's acknowledgement of the 9000 series' perfect operational record. Dave reluctantly sees Frank's point of view and reasons that if the AE-35 unit, once put back in place, doesn't fail as Hal predicted, then Hal would have to have his higher brain functions disconnected. Dave openly ponders about what Hal would think about this.
The scene shifts to Hal's point of view where it is apparent that Hal can't hear Frank or Dave, but is able to see them through the pod's window and read their lips. Hal knows what they're up to.
Mission Control has no appreciation for what Frank and Dave are going through. To them, it's a faulty computer, to Frank and Dave, it's more like a sick member of the crew who may have to be terminated. Mission Control just blurts out the possibility that Hal had erred - leaving Frank and Dave in the uncomfortable position of having to deal with Hal who had just been openly accused. The isolation due to distance and non-direct communication created a void between Earth and Discovery.
There is a lot of dishonesty displayed in this part of the film. Hal calls the situation "puzzling" but listen to how he says it. Up until now, everything Hal has said has been with a noticeable confidence. This confidence was even noted by Mr. Raynor, the BBC interviewer. For the first time, Hal is hesitant. We already know that Hal knew the AE-35 unit was functional and Hal had intentionally reported it as faulty. This means his puzzlement is an act. He also says "We can certainly afford to be out of communication for the short time it will take to replace it." With the hesitation in his voice, he sounds like a misbehaving child rationalizing with his parents in order to get his way. If a child "accidentally" broke his parent's car window, he might say "I'm sorry, I guess I won't be able to go to the Doctor today." Of course, losing communication with Earth is exactly what Hal wants.
Also notice Hal's emphasis when saying "human error" - he even repeats it. Hal is right, of course, it is the short-sightedness of humans that created the paradox in Hal's mind. Hal's emphasis on the word "human" indicates a hint of anger. Just as Hal is being accused, Hal is obliquely accusing his accusers.
This scene contains a classic Kubrick three-way conversation with tension.
Dave and Frank attempt to deceive Hal by play-acting the problem with the pod. Frank, like Hal, is a poor actor as his "What sort of trouble have you been having, Dave?" query is hardly convincing. Did it fool Hal at all?
We learn a lot more about Frank and Dave here. Frank is more obvious about his feelings. Frank, from the circuit test onwards, has lost faith in Hal and his facial expressions show this. Frank looks at Dave after Hal attributes the discrepancy to human error. When Dave appears satisfied with the answer, Frank jumps in with his own and much more direct line of questioning. He confronts Hal and tries to get Hal to reveal that he made a mistake. Frank would have to be an extremely intelligent person to have been selected for this mission but he lacks diplomacy skills.
Dave, on the other hand, is a much more complex character. He shows finesse in getting a response out of Hal without accusation. He does a good job of diffusing the building conflict between Frank and Hal. Dave is willing to see both sides and doesn't reveal what he is truly feeling until he has to. He is the only one of the two who considers how Hal might react to being disconnected. We already know that Dave is the mission commander but it is here where we see his leadership qualities.
This whole scenario can be seen as one big chess match (See The Chess Match and EVA). Hal has to solve his dilemma. He can solve it by cutting off communication with Earth by convincing Frank and Dave of a faulty antenna controller. If the antenna wasn't working, then this would be an emergency situation and Hal would have to disclose to Frank and Dave what the mission was all about - thus ending Hal's paradox.
To do this requires a series of steps (or chess moves if you will). Each step Hal takes depends upon how the humans (his opponent) react to his previous move. I already surmised that had Dave reacted differently when Hal was questioning him about the "extremely odd things about the mission", the whole faulty AE-35 scenario may not have taken place. What if Dave had accepted the fact that the AE-35 unit was faulty and didn't bother to test it or if Dave had assumed Hal was right and he had somehow missed finding the fault with his equipment? None of this state of mutual accusation would have occurred and Hal would be nearer to achieving his goal peaceably.
Unfortunately, Frank and Dave were thorough astronauts and came to the conclusion that Hal is a possible danger to them. Unfortunately, neither one of them realizes Hal's motive in suggesting another EVA. Hal's hand has been forced. Hal is staying a step ahead. Hal is winning the chess match.