Can a 7-Way Vehicle Side Trailer Connector Effectively Charge a Trailer Battery
Question:
Is this kit sufficient to allow the 7pin connector to charge the battery on our trailer I believe pin 4 is the charging pin. What pin does the 12 volt wire connect to in ETBC7? Also do you recommend a relay on the charging line? I heard the line should only be connected when the car is in motion. Or is it likely the converter box in my trailer is smart enough to break the connection when the line is not powered? thanks!
asked by: Sally
Expert Reply:
Pin 4 on the vehicle side 7-Way trailer connector is for 12 volt power on the 4 and 7 Way Installation Kit # ETBC7. The pins on a 7-Way trailer connector can provide a maintenance charge to a trailer battery but it cannot add additional charge. The wiring is not sufficient on the vehicle to up charge a battery.
On some vehicles, power to the 7-Way is terminated once the key is off and removed from the vehicle. On others, it will remain on. Since the ETBC7 has a direct connection to the vehicle battery via a 40 amp circuit breaker, the 12 volt pin will have power to it all the time. You would have to disconnect the trailer from the tow vehicle to avoid draining the vehicle battery.
Or you could install Battery Isolation Solenoid, # PK5231201, to isolate the vehicle battery when the ignition is turned off so that accessories on the trailer, like the battery in this case, will not drain the towing vehicle battery.
Products Referenced in This Question
Starter Solenoid - SPST - 12 Volt - 100 Amp - Continuous Duty - Grounded
- Accessories and Parts
- Battery Boxes
- Switches and Solenoids
- 100 Amp
- Pollak
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Product Page this Question was Asked From
Universal Installation Kit for Trailer Brake Controller - 7-Way RV and 4-Way Flat - 10 Gauge Wires
- Accessories and Parts
- Trailer Brake Controller
- Installation Kits
- etrailer
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