Brake Controller?

[RUFFSTUFF]

Upgrading the wiring on the Expy from 4-wire to 7-wire and I was wondering about the blue wire taped to the wiring. If I connect it for 7-wire use will I still have to get and install a separate brake controller?

 

[KWT2000]

yes you will still need a brake controller

 

[RUFFSTUFF]

Poop. So what good does the blue wire do? Save me a whole $1 from buying one on my own? Grrrrrr.

 

[KWT2000]

the whole plug and play harness should be factory in your truck saving you a good amount of cash

 

[Ray Jr.]

The blue wire should be back-up lights.
If you have surge brakes on the trailer the back-up light wire will stop the brakes from locking up when you back it up.

 

[RUFFSTUFF]

The blue wire should be back-up lights.
If you have surge brakes on the trailer the back-up light wire will stop the brakes from locking up when you back it up.

I'm not so sure about that.... Anyone else?

 

[KWT2000]

the wire would be purple if it was for reverse lights

 

[Ray Jr.]

On the 5 wire flat plugs for use with surge brakes the 5th wire is blue and it goes to back up lights.
I assumed it was what the op was talking about since he said it was taped to the harness wiring. Sorry was posting while half asleep.

 

[Stoned06]

On my 2006, the blue wire on the rear harness is for the reverse lights for surge brake lock-out when backing up too. There is an electric servo that prevents the hydraulic lines from pressurizing the brake line. Under the dash, the blue wire will still be needed for the brake controller (which is always necessary if you have electric brakes on your trailer).

 

[RUFFSTUFF]

Well... good info... I'm not gonna sweat it, just bought a Coleman travel trailer from Camping World and they are providing and installing the brake controller, weight distribution system and anti-sway bars for free.

 

[First Light]

On the 5 wire flat plugs for use with surge brakes the 5th wire is blue and it goes to back up lights.
I assumed it was what the op was talking about since he said it was taped to the harness wiring. Sorry was posting while half asleep.

Yes, a blue wire is normally for back-up lights. But when used with a trailer that has surge brakes, the blue/5th wire is energized when you put the transmission in reverse so as to by-pass the surge brake solenoid when backing, so the surge brakes will not engage when in reverse.

 

[mtondreo]

I tried putting a 12v light on my blue wire tonight while in reverse and got nothing. My expy does not have the factory heavy tow package but was looking for an easy way to get a signal to a rear camera. Can someone confirm this-maybe it is just low voltage or maybe I have to install some relays or fuses before that wire even becomes active. Thanks in advance, Mike.

 

[RUFFSTUFF]

The blue wire is not connected to anything on either end.

 

[ELVATO]

I tried putting a 12v light on my blue wire tonight while in reverse and got nothing. My expy does not have the factory heavy tow package but was looking for an easy way to get a signal to a rear camera. Can someone confirm this-maybe it is just low voltage or maybe I have to install some relays or fuses before that wire even becomes active. Thanks in advance, Mike.

Just tap into the reverse lights. Or, try the purple wire on your 7 pin round plug.