Finishing up this article, at approximately 3:00pm this afternoon while dodging rain drops and thunderstorms we completed the DUO install and placed the system in commission. In fact the process went so smoothly that concluding the install we were both looking for more stuff to do but that was it.
Since I did not have the motorhome available for a run test the only test that we could do at the moment was to pull the plug on the breakaway (BA) switch.
DUO Breakaway Switch on the Left and Blue Ox 6 Wire Umbilical Connection to the Right. Blue Ox Baseplate Extends Slightly Through Grill Openings.
Arriving this morning I uncoiled all the wires that were temporarily looped overnight and began figuring out where they would all wind up. We installed the BA switch in such a convenient spot that we didn't even have to drill a hole for it - the hole was already there! The BA switch is to the left of center and the umbilical connection from the MH is in the next recess to the right. We ran 2 wires from the BA switch over to the right of the vehicle and brought down the blue and the brown wire from the Operating Unit (OU) and butt spliced those connections.
Next a piece of 1/2" wire loom was fitted which over lapped the 3/8" wire loom that we ran over the joining pairs. I tie wrapped the run under the vehicle and that completed the work under the vehicle.
SMI Air Cylinder Fitted To Brake Pedal. Anchor Fastened to Firewall
12 volt power was taped and locked into the brown wire which runs down to the breakaway (BA) using a Scotch Block. The BA blue was tied into the blue coming down from the OU. The red and black wires from the OU were tied into the G-Force Controller II (GFC) color for color using butt connectors.
A separate wire from the inside of the vehicle (white) was required to be taped & locked onto the OU blue wire to activate the remote transmitter.
DUO - G Force Controller II. Kill Switch Is Located On The Top of the Unit.
The white ground wire from the GFC was tied onto the negative post on the battery. It's always best to tie in a ground at the battery. The 12 volt fuse holder was anchored on a + battery stud using an open eye connector. The other end of the fuse holder was taped and locked to the OU brown wire. (See above)
The remote transmitter harness has 2 wires a black and a red. This wire terminated into a female RJ12 connector. The red wire was taped and locked onto the white extra wire I ran inside the cabin that is tied onto the OU blue in the engine compartment. The black wire was taped and locked onto the GFC to the OU black. All that's left to do with the transmitter is to stick it on the windshield and plug the RJ12 male into the socket on the harness and that's it.
DUO Vacuum Assembly Fitted Into Boost Line.
Under the dash, I measured the DOT air line and cut it and pushed it into the air cylinder on the brake pedal. I chose to run it in such a way that it comes in from the left up high and drops down at an angle and made sure that it didn't interfere with any of the gear under the dash. We did the same on the OU.
If you need to remove the tubing you need to firmly push the small collar around the base of the tube toward the device, pull on the line and it will release. You can pull on the line all day long and it won't release believe me.
In all 6 wires run from inside the vehicle to under the hood plus 1 DOT air line.
Side View of DUO
The vacuum assembly consists of a check valve, 2 mini hose clamps, a T connector, 2 step up connections ½"¯ to 3/8"¯ and a couple of short sections of 3/8"¯ vacuum line cut off the OU. Beau made up the vacuum line assembly and set it aside. There was a rubber insulating wrap around the vacuum booster line that has to be slit off and reused.
He continued by cutting 3 to 4 inches out of the existing brake booster vacuum line in front of the engine with a hose cutter. He then added the sub assembly that was made up which measured about 7 to 8 inches long. There was enough room to fit the vacuum hose assembly and re-wrap the new hose assembly with the previously removed wrap. 2 mini hose clamps were used on the 1/2" diameter side of the adapters where the assembly ties into the existing booster hose.
DUO and Fuse Cover Flipped Over On Air Box Plenum
The hoses need to be firmly pushed into place and none of the barbs or the fittings themselves should be visible after pushing everything together. The check valve is marked engine and that's the side that faces the source of the vacuum.
Once the insulating wrap was tie wrapped in place it looked like it could go the distance. I started the car just to check for vacuum leaks – none found - no problem.
Earlier there was a tense moment when we were picking short straws to see which one of us would actually be sacrificed to socket the 15A fuse that comes with the unit. I opened the cap on the in-line fuse holder and put the fuse in and a whole lot of nothing went on! This I'm told is a good thing.
DUO Installed and Wire Loomed
Confirming that nothing occurred, I then reached inside the car to toggle the cut off switch on the top of the GFC. The switch was in the OFF position and I winced a bit and pulled the toggle toward the inside of the car and turned the system "ON" - still nothing! GREAT!
We stood back and admired the job for a moment and now it was time to go for the gusto! I reached down to the breakaway switch lanyard and gave it a good pull and the compressor kicked in and the brake pedal was pulled in toward the firewall as witnessed by Depchief (Beau).
Exhibiting Low Profile Underhood
I believed that we did a very good install. We ran as much wire as possible through wire loom and taped and tie wrapped everything. The OU however has to remain movable since it sits on the top of the fuse cover. What we did is to measure and fit all the cables and air and vacuum lines so the unit and cover could be lifted and rolled onto its back on the top of the air plenum box for servicing inside the fuse panel. Works great.
The next step is going to be to hook up the car behind the motorhome and test the system while underway. Setting the gain I understand is straight forward however I have to review the exact procedure before we tow.
Direct to Battery Ground - Best Bet
Linear Mode
