Boat Trailer Part Failures

The most common boat trailer part to fail is the boat trailer electrical system. Like many I have experienced frequent issues, and they need to be checked and maintained regularly.  It is subject to frequent water ingress into light fittings and lighting connectors almost every time you launch or retrieve your boat.  Also this has the effect of rotting out the copper electrical cables so they tend to need rewiring on a regular basis. Copper doesn't last long with salt water as you know. 

Boat Trailer Part Failures

The next most common boat trailer part failure points are the wheel bearings, subject to salt water ingress and corrosion as they sit in the back yard for long periods and tend to seizes up. Most wheel bearings are of the sealed type but that doesn't stop water ingress.  

Initially the balls corrode at the contact point with the race and when they rotate the material flakes off, the heat is then generated with the friction and ultimately the bearing grease runs out and the bearing fails. This is usually while on your way to a good day fishing.

So what does this mean for you the boat owner, well if you don't look after your boat trailer you end up stranded at home when the season starts, or worse still you get left stranded at the boat ramp. If you are really unlucky your electrical lights on the trailer fail and the highway patrol shows little sympathy and gives you a fine.

Boat Trailer Part Wiring

The UK and Europe use ISO Standards with two 7 pin plugs. Wiring harness are based on the EU 13 pin plug that is common on mainland Europe. 

12N Socket Standard

1 (L) – Yellow - Left hand indicator light

2 (54G) – Blue - Rear fog light

3 (31) – White - Ground/earth

4 (R) – Green - Right hand indicator light

5 (58R) – Brown - RHS Tail/Licence plate light

6 (54) – Red - Stop (Brake) light

7 (58L) – Black - LHS Tail/Licence plate light



12S Socket Supplementary

12S Socket Supplementary

1 Yellow - Reverse Light or Brake System

2 Blue - Spare

3 White - Return for Pin 4

4 Green - Power Auxiliaries/Battery

5 Brown - Warning Lamp

6 Red - Refrigerator

7 Black - Return for Pin 6

Get the right boat trailer part for your boat trailer information and advice on boat trailer parts.