What Does Flashing 0.9 Mean on Prodigy P2 Brake Controller

Updated 12/23/2024 | Published 09/19/2017

Question:

Break system says small zero. 9. Flashing what does this mean

asked by: Jed

Expert Reply:

On the Tekonsha Prodigy P2, the 0.9 error code you describe is caused by the controller losing connection to the battery ground. Make sure the white wire exiting the rear of the controller has a connection to the negative battery terminal. If the controller has been hardwired, check the connections on the ground circuit and where the ground connects to the battery. Make sure the connections are tight.

expert reply by: Jameson C

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Gayle

12/20/2024

Would this error code cause the blinker light on the trailer to flash alternately instead of a steady blinking on and off? We got that error message and it went away right away, but now the blinker is acting up. Our device was hard wired in many years ago. Thank you.

Jameson C.

12/23/2024

@Gayle Those two issues should be unrelated but it might point to something going on with the wiring of the truck. If the truck has a weak ground that would cause the brake controller to have a weak ground error and then also potentially COULD be part of the trailer light issue. Sometimes a weak trailer ground will cause bizarre issues with the lights. So with those two things together it could indicate maybe a loose terminal on the negative post of your vehicle battery.