Troubleshooting Electric Tongue Jack Not Working When Connected To 2019 Ford F-150

Updated 07/07/2023 | Published 07/06/2023

Products Featured in This Question

Hook Probe Circuit Tester

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Replacement 12V 10 Ah Battery for Bright Way Trailer Breakaway Kits

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Question:

I have a 2019 Ford F-150 with the tow package. I recently installed an electric TowingMaster marine jack on my boat trailer with a 7-way plug. The jack handbook says the power is at # 4 and the ground is at #1. I can get power to the jack after holding the brake on the pickup to get the trailer connected sign on my pickup. The light comes on, on the jack but when up operate the up/down buttons, it does not work. The book says it needs 10 volts to work. Does this mean my pickup is not transferring at least 10 volts to the jack? What would be some suggestions? Thanks

asked by: Ron M

Expert Reply:

It sounds like you may have the power and ground wires reversed. I have included an image below for the terminals on a 7-way connector so you can verify you are connecting to the correct wires on your trailer connector. The power terminal is located at the terminal in the 1 o'clock position while the ground is located at the 7 o'clock position when looking into the vehicle 7-way. Your 2019 Ford F-150 requires tow / haul mode activation and / or load detection on 7-way before the +12V output is activated on the 7-way connector. Activate tow mode and connect trailer before attempting to operate the jack. A Test Light # PTW2993 can help you confirm you are getting power on the correct circuit as well for the jack.

It sounds unlikely your F-150 is not transferring enough voltage but it may not have large enough wire for the amp draw required. This could also appear as low voltage when the motor tries to pull the power it needs. You may need a Battery # BRW87FR to the trailer to be able to provide additional power to the jack which can recharge off the vehicle when being towed.

expert reply by: Bud M