Narrative:

During the preflight; I paid close attention to some previous write-ups because the brakes have been previously written up just a few days prior. After leaving the gate; I pressed my brakes as instructed by the normal procedures handbook. I did not feel any resistance at all on the brakes; but decided to pump them several times to see if that would improve the situation. I made this decision because sometimes the brake fluid is thick when the aircraft is cold. I wanted to determine if the copilot brakes were connected to give a proper description to maintenance. Unfortunately these actions did not help. When we began our runup; I instructed the first officer (first officer) to hold the brakes with me to see if we had any braking control at all. The airplane began to roll at 1700 rpms despite both of us holding the brakes. At that moment; I informed ATC that we would be returning to the gate and that we would have to cross the runways; but had little to no braking action. We received clearance to cross both runways and made a successful gate return.

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Original NASA ASRS Text

Title: C402 Captain reported returning to the gate for maintenance when the brake system malfunctioned during taxi and run-up.

Narrative: During the preflight; I paid close attention to some previous write-ups because the brakes have been previously written up just a few days prior. After leaving the gate; I pressed my brakes as instructed by the normal procedures handbook. I did not feel any resistance at all on the brakes; but decided to pump them several times to see if that would improve the situation. I made this decision because sometimes the brake fluid is thick when the aircraft is cold. I wanted to determine if the copilot brakes were connected to give a proper description to Maintenance. Unfortunately these actions did not help. When we began our runup; I instructed the FO (First Officer) to hold the brakes with me to see if we had any braking control at all. The airplane began to roll at 1700 RPMs despite both of us holding the brakes. At that moment; I informed ATC that we would be returning to the gate and that we would have to cross the runways; but had little to no braking action. We received clearance to cross both runways and made a successful gate return.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.