Troubleshooting Prodigy Brake Controller Installation in Mercedes-Benz Metris

Question:

Mbz metris,working well until activate turn signal,shows flashing 0.0,until signal released,disconnected turn signals at connector box still happening but not all the time.

asked by: Chris C

Expert Reply:

A brake controller like the Prodigy P3 # 90195 interacts with only one lighting circuit on a vehicle, the circuit for the brake light switch, which is typically above the brake pedal. This brake signal triggers the controller output for the trailer.

Turn signal lights on the car are not required to connect to the controller in any way so if this light function is affecting the operation of the controller then it is possible that there is a short in the 7-way socket or the wiring leading to it.

Check your 7-way for signs of corrosion or trapped foreign material that might be causing the brake circuit to become bridged to the turn signal circuit. If you refer to the linked photo of a trailer connector you will see that the brake circuit at the 5:00 position is right next to the right turn signal circuit. You can try cleaning the socket or replacing it with # 37185 if it is badly corroded.

You can also refer to the linked article.

expert reply by: Adam R