Troubleshooting Blown Brake Light Fuse When Towing Roadmaster Tow Dolly Behind RV

Updated 02/07/2019 | Published 02/06/2019

Products Featured in This Question

Roadmaster Tow Dolly with Electric Brakes - 4,250 lbs

(11)

$3525.00

14 Gauge Wire - Yellow Primary - Per Foot

(51)

$0.68

Deka Heat Shrink Butt Connector - 16-14 Gauge - Nylon Insulation - Blue - Qty 5

(1180)

$8.90

Question:

Have recently purchased a Roadmaster RM3477 tow dolly. I have it wired on the RV connector as noted in the attached diagram. The dolly connector was factory wired. Running and turn signal lights work fine, but after applying the brakes I am blowing the brake light fuse on the RV. When I disconnect tow dolly jack the RV brake lights work fine. Appreciate any help.

asked by: Paul D

Expert Reply:

It sounds like you have a short somewhere on your brake light circuit. Since your Roadmaster Tow Dolly # RM-2050-1 is newer I believe the problem is on your RV.

Start off by checking both the connector on your tow dolly and your RV and make sure that the pins which carry the brake signals (on either side of the connector) are in good condition and don't have any corrosion. If these look good then you will want to check the wiring itself. Look for any places that have exposed or bent wiring and replace as necessary. For the brake light circuit you would just need 14 Gauge Wire # DW02412-1 and butt connectors like part # DW05744-5.

I have attached a troubleshooting helpful article for trailer lights but this will still apply to your tow dolly application.

expert reply by: Jon G