DougE

To install a trailer brake controller there are (for Prodigy II) 3 wires to hook up to the van's electrical system plus the wiring going to the trailer brakes - brake power, ground, brake signal and trailer brakes. All sources are straight forward except for the brake signal. Normally you pick up the brake signal from the brake switch at the brake stop light switch. On the 2010 Express there are four wires coming off of the stop light switch. The stop light signal is normally 12v and goes to 0v when the pedal is pushed. This will not work for the brake controller. A second pair of wires provides a brake signal to the transmission and is normally 0v and goes to 12v when the pedal is pushed. This is the wire you need to connect to. On the 2010 express van this is a light blue wire with a white stripe in the "D" position on the 4-way plug. You can back probe the connector with a test light to verify the wire that goes from 0v to 12v when the brake pedal is pushed with the ignition switch on.

rdw123

Sadly, on the 2012 that plug (on the brake pedal) is replaced with a different set of wires that are all signal level, not 0-12v. On the 2012, you can catch the blue with white stripe over on the BCM (Body Control Module) which is over on the passenger side behind the knee panel for the dash.

I will look up the specific plug you can find the wire on, it is a mess of wires in there and you may need to pull the BCM out a little before you can see the actual wire in question. Just had to connect to it for adding a remote start system and spend quite some time with multiple tech supports before they got me over to the BCM. UG.

Will have more in a little while on wire location... (I am also adding a trailer brake controller soon and will need to connect to it for that too... )

DougE

Pickups have a plug for easy hookup. I don't know why they discriminate against us van users and make it so hard on us.

rdw123

The plug would be there if your truck had the full tow package in its original build.... ah well

Paulieboy

Hello rdw123, did you find the color of the connector, containing the blue and white wire needed to wire in a brake controller on a 2012 Chevy Express 3500? Thanks

rdw123

the wire is labeled light blue with white trace, on the brown BCM plug (between the black and pink plugs) (the wire will be +12v when engine on and brake pedal stepped on)

Make sure you are on the brown BCM plug.

Some say the yellow wire on the brake pedal switch plug is the one, and yes, technically it is, but it is a signal wire (going from 1-1.2 v for me) where the above bluew/white wire on the BCM is 0 or 12v which makes the brake controller happy.

Careful when probing wires, must use a "computer safe" probe, typically a led rather then a regular bulb, but it will be labelled on the package. a digital voltmeter will work too. Otherwise you can trip the check engine light.

Have fun!

R

DougE

Amazon has a Amico DC 6V-12V LED test Light for less than $6. Not sure how good they are but I ordered one for use on my modern vehices. They lied! It's just a regular filament bulb.