Thread: Trailer wiring - blue "service brake" wire

I'm looking to tow a small caravan for the first time, but large enough so that it has electric brakes. I have a 7-pin plug/harness fitted, and it looks to be the one that plugs into the LR plug/loom. All lights working fine. BUT I do not get a signal on the blue "service brake" line when I step on the brake (tested via multi meter). And, the car does not have an electric brake controller.

So, just confirming some threads I've searched up:

- Am I correct in assuming that even though the car has a plug with the blue wire attached, it will terminate in the block up behind the plastic flap in the RHR wheel well and stop there?
- (If first point wrong) I don't suppose the standard loom does happen to run the blue wire forward to the front of the car somewhere?
- And assuming all the above fail, and I need to install a controller, is either the Redarc Tow pro or the Tekonsha still the recommended way to go? With a suitably heavy cable for the blue line run to the back of the car?

Thanks in advance yet again!

We have a Tekonsha running to a 12 pin plug on the back of the Defender, and the van has a 7 pin plug that plugs into the lower row of plugs on the 12 pin.
I like the Tekonsha because it can be set to work on a scale - ours is set to 0-5. The display shows the pedal pressure at a glance, unlike the Redarc. Ours is set the brake the van harder than the vehicle for stability when towing.
There is a separate Anderson plug connection to charge the van's Endrdrive lithium battery and DC-DC charger. The vehicle sends 8amps to the DC-DC which boosts it to 40 amps. Works well.
Hope that helps.