During cross-examination at the FIA's International Tribunal hearing in Paris on Thursday, Brawn said that there was no way his outfit could have benefited from the testing data.
"I don't see how," he said. "We didn't know what the tyres were; we didn't know what the detail objectives were of what Pirelli were doing.
"We always work on the principle that no information is better than bad information. I don't see how we could have used any data from that test."
Brawn clarified that car telemetry at the test was kept active for safety reasons, but had subsequently been archived in a secure server at the team's Brackley headquarters to guarantee that it could not be used.
"It is essential that the team keep a track of what is going on with the car when it is running to ensure there is no malfunctioning, or some issue with car," explained Brawn.
"The telemetry was used for normal functioning of car."
When pushed by the FIA lawyer on the fact that any running time with a current car is a benefit, so Mercedes must have gained knowledge, Brawn said: "I think that is unavoidable, and was a consideration taken into account when we had permission from the FIA to do the test. But it does need to be kept in proportion."
Brawn also made it clear that he always considered the opinion of F1 race director Charlie Whiting on sporting matters to be final.
"Charlie is the go-to reference for all the sporting matters, particularly when at a race track because there are numbers of issues that come up on a race weekend, and Charlie deals with them as race director.
"The important part of sporting regulations is it is something that does need a timely response during the event, so if we had a situation where for sporting regulations clarification or checks that had to go through a procedure then there are a number of areas that would be quite difficult."
Although the FIA questioned why Mercedes had not followed up discussions with Whiting on the permission of running the 2013 car, Brawn said such a state of affairs was not unusual.
When asked if he always followed up Whiting's views in writing, he said: "No. Particularly during the period of an event, a race weekend, that is not practical."