Wiring Schematics - “Customer Interface A” Connector

[flyboy013]

I’m in the process of adding some wires behind the dash up in the front left corner for an electrical compartment driver’s window switch and for an USB outlet at the A pillar.

In have managed to pull a wire/pin out a connector and cannot figure out which of three empty connector holes the pin belongs in. The connector is a 12 pin connector (3x4) with a mating connector that is labeled “Customer Interface A”. Some of the wires are labeled but most are not. Some of the labels are: Radio-2, Chassis, Chassis 51, CTSY ???, and BATT BST (?) RLY.

I’ve been in contact with Newmar and they recommendation tracing the loose wire to see which component it connects to because “Unfortunately there are a thousand wires under the dash and we don’t have prints for all of them”. I’m a bit shocked that they don’t have the schematics, but not much I can do about it.

I’ve attempted to trace the wire and unfortunately it feeds into a 3-4” diameter zip tied bundle with 200+ wires. Before tearing things apart I figured I’d ask to see if anyone is familiar with the “Customer Interface A” connector and where it might lead. Disconnecting the connector cut the power to the radio but I don’t see any wires near the radio that are labeled the same as the wires on the connector.

There was another post that indicated that Newmar uses the same harness for all the coach, but with fewer pings used due to what capabilities are installed on each coach. So if you have any pictures of the connector (which may show where my loose pink wire goes) or have first hand knowledge of these particular wires/connector your input was be greatly appreciated.

I haven’t yet figured out what’s isn’t working.

[ATTACH][ATTACH][/ATTACH][/ATTACH]

[Skip426]

Just a few comments ;
First be very careful in there with a ring on your finger , even a fused 12 volt circuit can give you burns in a hurry.
The locating barbs on the pin , do not ( from what I can see in the picture ) appear to be damaged , so it may not have been properly installed in the connector in the first place. I've dealt with those connectors , even with the proper removal tool they're difficult to get the wire out.
It's a { self edit } that the wiring colors don't match on each side of the connector; what were they thinking .
After being , over , under , around and through my dash wiring for 9 years , and finding a multitude of open ended wires for uninstalled options ( there are 9 empty fuse sites on my dash power distribution board ) particularly if you can't find any non operational items , don't be surprised if that's just an unused wire.

[Dutch Star Don]

I'm going to ask a dumb question. Can the three holes be eliminated through a "process of elimination"....ie….are there wires in those matching holes on the other plug. Is there a matching colored wire on the other plug. Does that wire that came out change color or have a second wired toed into that matches a wire on the other plug. Sometimes they tie two wires together and the matching wire on the other plug only matches one of the two. This also works the other way, wire on the other plug has two wires tired together that match.

[flyboy013]

Thanks for the responses. Given that the wire has a connector pin as opposed to terminal connector, I’m fairly confident that the wire can out of the connector as opposed to being for an option that’s not installed. I’ve found plenty of those other wires.

I’ve looked for marks within the connector holes as an indication of which hole the wire may have been in, but no luck. The wire was taped in a bundle with the other wires that go to this connector, so I’m fairly it belong in the specific connector. The matching connector has wires in all 12 holes and the wire colors don’t match up with the mating connector.

Given that one of the wires in the connector provides power to the radio, I was hopefully that it is a radio related wire. I’ve checked all the speakers (left, right, front, and back) and they all still work. I’ve found a few connectors behind the radio which when disconnected cuts the power to the radio, so it seams that at least the radio power wire passes through several connectors which tells me that the wire may split off somewhere and may not be radio related.

I’ve purchased a wire tracer, but given the bundle of wires (3” diameter) behind the instrument cluster, it’s very difficult to isolate the wire as the other wires are carrying the signal too.

I’ve begun to carefully unbundle the wires behind the instrument cluster in an attempt to isolate the specific wire. Unfortunately, the wire appears to be at the bottom of the bundle with a fair number of zip ties holding the various smaller bundles together in a larger bundle.

I’m VERY disappointed that Newmar doesn’t have schematics available. I find it hard to believe that they build the coaches without them.

I’m hoping that someone may have taken pictures of some of their wires in the past and may have captured the “Customer Interface A” connector. Alternatively, looking for troubleshooting techniques that may help me figure out where the wires goes. I’m at a bit of a loss.

[C.Martin]

I had the problem of finding out that Newmar never connected the wires to my Mirror Heat Switch. I found lots of extra wires behind the dash with no clue...other than one, which said mirror heat. I also had no clue which wire went where on the three terminals of the switch. Between the Customer Service sending the harness schematic...which identified the three wires...and the kindness of NealC taking photos of the wires connected to his switch...and sending it to me, I was able to get it working.

It is going to be a monumental task...unless, the kindness of another 2017 MADP comes along, wiling to disassemble their dash to find the “customer interface A” harness...and photograph both sides of it for you. In which case you’ll have what you need in seconds.

[bruceisla]

CTSY is the Courtesy Lights (the lights in passageways at floor level) usually a switch in bedroom and a switch on dash.
BATT BST Relay is the switch for Battery Boost (ties chassis and house batteries together). Mine is a switch on dash. The other end of that wire will go to your Big Boy Relay.

[flyboy013]

Originally Posted by bruceisla

CTSY is the Courtesy Lights (the lights in passageways at floor level) usually a switch in bedroom and a switch on dash.
BATT BST Relay is the switch for Battery Boost (ties chassis and house batteries together). Mine is a switch on dash. The other end of that wire will go to your Big Boy Relay.

Thanks.

While I'm not sure where the Courtesy Light wire would be going at the dash area, I would assume the battery boost wire goes to the battery bridge momentary switch on the dash. This will give me another place for me to work backwards from to find the connector at the other end (assume there is another connector and this isn't just a pigtail going to the various switches and devices).

[Mr_D]

The wire labeling (or lack of) was one of my major complaints about my Dutch Star. Then there were the undocumented inline fuses!!
Present CC has all wires labeled and the wiring is all polarity correct.

["007"]

On my 2003 coach all wiring was labeled as to where the wire came from and where it was going.
Many complained they didn't have that so I started digging into wiring of coach's.
The wiring does not change that much in older coach's but newer ones are loaded with so many options and they seem to use the same wiring harness for multiple coach's.
Older coach's had wiring and fusing in their Owners Guides, later coach's had same wiring & fusing tables that I used from 99 to 2007.
This link from the large sticky top of forum has what I use most of the years I have been here.
Looking at all the training links seen in the Com_Net pages have not ever seen a reference to wiring systems by Newmar so do not expect any change in the future.

[FatChance]

My guess is that connectors like that have one side of the connector that is a generic set of wires that comes from the chassis and the chassis manufacturer (Spartan in this case) designs it in a way that may support many different coach manufacturers and models so they are just assembled as a generic bundle that might be used in many ways. The other side of the connector is the coach builder's wiring system that interfaces with the generic chassis bundle. That is probably why the wire color coding does not match and there is no definitive wiring diagram available.

Motorcoaches are different than cars and most smaller trucks in that, instead of building the whole vehicle, the coach manufacturers purchase the chassis from a separate company that supplies chassis for multiple coach and truck manufacturers and models.

The "customer interface" refers to Newmar as the customer, not the coach buyer.

[bruceisla]

Originally Posted by flyboy013

Thanks.

While I'm not sure where the Courtesy Light wire would be going at the dash area, I would assume the battery boost wire goes to the battery bridge momentary switch on the dash. This will give me another place for me to work backwards from to find the connector at the other end (assume there is another connector and this isn't just a pigtail going to the various switches and devices).

I have a switch at the dash panel labeled "CTSY LIGHTS". Mine is in the same panel as Visors and Shades. If you have the switch you could check for functionality. My lights are 6 inches above the floor and run down the hallway. They are similar to lighting along the steps in a movie theater. I have another switch in the bedroom near one of the nightstands.

[flyboy013]

Originally Posted by bruceisla

I have a switch at the dash panel labeled "CTSY LIGHTS". Mine is in the same panel as Visors and Shades.

I usually turn on/off the courtesy lights from the bedroom KIB panel, but as you stated there is a courtesy light rocker switch with the shades and visor switches. I don't use the courtesy lights much. The courtesy lights are working just fine.

I determined that the windshield overhead fans are not working. Its the only things I've yet determined isn't working. Using the multimeter I determined that the loose wire has continuity to ground. I connected the wire tracer to the loose wire and put the probe in the vicinity of the backside of the two OH fan switches (on/off, low/medium/hi) and I wasn't hearing the pulse, so I still a have more work to do, but I'm getting closer. I'm making a diagram of the OH fan wiring to help me troubleshoot. I'll double check with Newmar on Monday for a schematic specific to the OH fans. Since I'm being more specific perhaps they will have something.

I was looking for the fuse for the OH fans so that I can make sure that the reason it wasn't working was the loose wire as opposed to the fuse. I didn't see anything labeled as such in either the power reel compartment or the front drivers side compartment. Some posts have indicated that it may be tied to the dash AC fans, but I'm not sure. Interested in feedback from anyone who has had blown fuse in the past for the OH fans.

Getting closer. Thanks!

["007"]

The over head vents for windshield are fed from blower in your overhead cabinet behind a wood panel.
Fan is controlled by a three way switch, high, mid, low. on the horizontal dash panel.