DIY: 2017-19/20 classic Overhead Mic and Compass harness install

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Mpgrimm2

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Coming soon.

DISCLAIMER: I am not a coder, developer, software guru, electrical engineer, etc. but I did sleep at a Holiday Inn Express once!

I've got 2 members that will be testing/documenting the install of the mics in the headliner on the 17+ 4th Gen trucks to go along with their 8.4 conversions ( & 1 adding Compass module also).

This will not cover adding in the full overhead console's lighting since the power and the 2 separate lighting signals for that come from all over the cab/different locations and isn't practical for a standard harness I'd build (at least for now).

I'm going to grab the first several posts so things can be updated/rearranged later at the front of the thread.

@rangemaster728 and @likes2build please post up anything you feel is relevant here and we'll get it sorted it as we go.

Preliminary mic harness (w/compass module) shown below...

Basically installs at green “INLINE-HEADLINER LT/IP” connector behind the driver's side air vent and will route up the 'A' pillar and across the front of the headliner. You will need to remove the 'A' pillar, visors, and partially lower the front of the headliner to run the harness and also carefully cutout the openings to install the Mics and Compass module.

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Mpgrimm2

Mpgrimm2

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Post 2 for me.

6EP09BD1AA - mic, Grey (Std Headliner)

6EP09DX9AA - mic, Black (ie black out/headliner)



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Mpgrimm2

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Post 3 for me.

OEM Mic locations...
e57bb539b67bd67ae40d8fd39541590e.jpg

368e8d08ec4ea4dd4f79ea3f9360ffc7.jpg

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Mpgrimm2

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Post 4 for me

@R.L.K. 's way earlier compass thread on his 14 ram1500 from a few years back as Additional reference... Finally found it here.


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Mpgrimm2

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Post 5 for me .. that probably a good enough start.

Carry on

Edit. . . Reference for the Driver side Inline-body Headliner Lt/IP connector behind the driver side air vent.

6ef703abce68c431178b6845fcac4441.jpg420daa3bb235335ecdb39b5d5474f9cc.jpg
 
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rangemaster728

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In my particular case I have a 2020 Ram 1500 Classic Tradesman 4WD, Quad Cab...it came with the basic RA1 radio. I changed out the RA1 for an RA2 radio and I wanted to add headliner mics and a compass module, but did not want to add an overhead console.

I’m an electrical engineer and do a lot of side work on BMW motorcycles, mostly electrical items including Canbus control. I am very comfortable doing wiring and connectors and have most of the crimp tools and pin extractors needed for these jobs.

In looking at the wiring diagrams I reached out to Mpgrimm2 (Mike) about building me a specific harness as he is very experienced in building Ram harnesses of this type and just a great guy!

In my specific case the circuit diagrams show the dual mic setup like this...NOTE: it is recommended you verify the wiring on your particular vehicle as harnesses and wiring colors vary from some years to others, I traced out all mine:

05afcaa4b88524300071fc5968fc799d.jpg


And compass circuit like this:
3f9b290124aa41d66490aed6c3959a7f.jpg
Note this diagram only shows the one-wire LINbus connection..there are actually 3 wires needed, the other 2 being B+ and ground. We’ll get to that.


As Mike mentioned in my case the wiring harness involved is the LT/IP up the left side, just below the driver side A pillar; the only wiring I had going up to the headliner was pins 11 (dome light) and 16 (black ground wire):
746f24b648e4121931c1212c48eed6a0.jpg



LT/IP connector wires found in place on this vehicle (male pins/vehicle side); pins in positions 1,2,7,8,9,10,11,15 & 16:
bedd0e65ec78d3a728987f7be69ce5c7.jpg


9d85fbe0f75d23d123494bc2d830d2ea.jpg



1 RED FUSED B+
2 ORANGE/VIOLET LINBUS CBC 2
3 NC (no connection)
4 NC
5 NC
6 NC
7 BLUE/GREEN MIC 1 (-); other end traced to RA2 connector, pin 29
8 BLACK/GREEN GROUND
9 BLUE/BROWN HS MIC IN 2 (-); other end traced to RA2 connector, pin 39
10 BLUE/GREEN MIC IN 2 (+); other end traced to RA2 connector, pin 40
11 YELLOW/VIOLET COURTESY LAMP DRIVER (in use)
12 NC
13 NC
14 NC
15 GREEN/BLUE MIC 1 (+); other end traced to RA2 connector, Pin 30
16 BLACK/GRAY GROUND; USED FOR COURTESY LAMP DRIVER (in use)


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rangemaster728

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To continue...

The dual mic circuit involves four connections, shown in previous schematic...these terminate at the rear of the radio:
ef7ade5fd021dc27366b3d41289999d0.jpg

COLORS ON DIAGRAM ABOVE:
Pin 29 Mic 1(-) blue
Pin 30 Mic 1(+) green
Pin 39 Mic 2(-) brown
Pin 40 Mic 2(+) grey

Here's the correct wire colors... (It's still a good reference for the layout at the backside of the radio):

29 BU/GN MICROPHONE 1 IN (-)
>>> (Blue/Green Stripe) to i370-7

30 DG/BU MICROPHONE 1 IN (+)
>>> (Dark Green/Blue Stripe) to i370-15

39 BU/BG HANDS FREE MICROPHONE 2 IN (-)
>>> (Blue/Beige??? Stripe) to i370-9

40 BU/DG MICROPHONE 2 IN (+)
>>> (Blue/Dark Green Stripe) to i370-10

Mpgrimm2 built me up a harness (he has a pic up in this thread) that provides the proper connections in the harness going up the A pillar to connect both the compass module and dual mics.

The back of the radio harness already had the aforementioned pins populated and wired to the lower LT/IP header and I verified they went to the appropriate places on the radio connector, so I was good on that account:

cc69bf86987bb2613657424f55640df9.jpg



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rangemaster728

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And to continue...

The compass module wiring is pretty straightforward.
The compass needs 3 connections; B+ (power), ground and a data connection (Linbus CBC 2); the compass does not connect to the vehicle Canbus, but a separate data network in the vehicle called Linbus.

Linbus is an older, slower network that is used for some devices in our vehicles, but does communicate with various modules thru the truck networks.

The three connections at the module (B+, ground and Linbus CBC 2) are routed up the LT/IP header on the harness I had M2M Mods make:
(Pins on vehicle-side harness)
Pin 1 - Fused B+
Pin 2 - Linbus CBC 2
Pin 8 - Ground

The compass module was obtained from a donor vehicle; this part number shown is correct for a compass-only module (68105281AB)...the compass/Homelink module for 2013+ trucks is 68105822AB, but then you’d need a full overhead console install and more wiring:
cff81451a5ae8b86a92d3c05b7f26cdd.jpg

I marked it for orientation (with respect to how it sits when installed in an overhead console).

The compass module end connector is a readily-available one; PT2779 AC Delco Pigtail for compass module.
51ec4024ad4274640aa75beb9a634d67.jpg



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The pigtail has four wires...I only need three for this mod:
Pin 1 - Fused B+
Pin 2 - Ground
Pin 3 - Linbus CBC 2
Pin 4 - not used.
6e7121d437be69a0c5ff7c344dee6bae.jpg

(EDIT: Mike now has incorporated the compass module connector into his harness design!)
 
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rangemaster728

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Now to the routing...

Remove the A pillar and thread the new harness down towards the LT/IP connector:
09e2369a0eb4c1569386ff4cae324c4a.jpg

After getting the LT/IP connector where I can work on it (I found by just opening the access panel on the left side of the instrument panel by the door I had enough room after pulling the xmas tree retainer for the plug) I inserted the sockets into the connector heading up the A pillar:
1b9ccff1a03619da5ed83578765623ec.jpg

Pics of the upper connector after adding the new harness for the mics/compass.

Wires added...
pin 1 is right end, red wire, Fused B+
pin 2 orange wire, LIN CBC 2
pin 7 blue wire, MIC IN 1(-)
pin 8 black wire, ground

c17e85a78741f3f3138b6099d3816f75.jpg

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Other side of upper connector; pin 9 is brown wire on the left, pin 16 is black wire on the right:
8b0079858106af1a8f10e6ef2102a860.jpg


Wires added...
pin 9 is left end, brown wire, MIC IN 2 (-)
pin 10 grey wire, MIC IN 2 (+)
pin 15 green wire, MIC IN 1 (+)


NOTE - READ THE INSTRUCTIONS ON HOW TO REMOVE THE TPA CONNECTOR RETAINER AND INSERT THE SOCKETS IN THE CONNECTORS - UNLESS YOU ARE EXPERIENCED IN THIS...M2M includes a nice summary with his harnesses.

I decided NOT to pull the visor and visor clip yet because I wanted more headliner support when I did my mic cuts.

I made a template and located the areas I wanted to cut for mic insertion - I went further inboard than factory (my choice):
0a8bfd5b80b1712df40669171c8b45ed.jpg

Using the template (and nitrile gloves to not get dirt/grease on the headliner) I drew the cutout locations and carefully used a small razor knife, taking my time. The headliner is thick, so multiple passes are necessary.

d646060cc7e3c8e22ea7afc20f6bf3c3.jpg

Do a test fit with the mics...I had to enlarge the hole just a bit but wanted a snug fit and no wiggle. Repeat for passenger side.

I then removed the visors, visor clips and passenger side A-pillar to be able to pull the front of the headliner down a bit and routed the harness up the driver side pillar. Secured the harness up the pillar with small wire ties.

For routing above the headliner I wire tied the harness in several places to sticky back wire anchors...here’s the basic idea:


1ac8977c587a9434a9d2a9543a954605.jpg

Routing the harness above the headliner I’d peel off and stick them up there to the headliner so wiring wouldn’t flop around.

To avoid creasing the headliner I fished the mic connectors out the holes I cut using a flexible grabber tool...worked great:
fdac56a71fb13499d7a22b905d2756f1.jpg

The mics (6EP09BD1AA) were a perfect color match for the headliner.
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d8d60172d5304b160e42bc27fdaf5612.jpg

Compass mounting, mic and compass programming details posted shortly...need more coffee!


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rangemaster728

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Compass mounting...

I recommend you disconnect the negative battery terminal prior to doing any termination or harness routing regarding the compass module... not only safer, it helps when you get to programming the truck to recognize the module (see programming post further down in this thread).

NOTE: If you are using a ‘repurposed’ compass module you might want to do the programming first and verify you have a good module before anchoring the module and reattaching the headliner; while these modules rarely go bad it saves some time if you have a problem. See programming post below (will put it on shortly).

Again, I advise you wear nitrile gloves so you don’t get the headliner dirty.

I connected the 3 flying leads for the compass from the wiring harness M2M Mods provided to the compass pigtail using Posi-Taps, then heat shrinked the three connections. Also used the same wire tie/stick on procedure as the mic wires so things stay put. (EDIT: Mike now has incorporated the compass module connector into his harness design!)

I took the compass module (oriented as it would be if installed in an overhead console) and applied several pieces of 3M Dual Lock; I use these on bikes and the outdoor type appears impervious to heat and humidity:
33f593cf2cf3fc13371cc5bcd8de5c4c.jpg

Attaching the dual lock to the underside of the module...and mating it with the opposing piece, you can then peel off the adhesive cover and carefully insert the compass module in the headliner at the front...about where it would sit if you had an overhead console. Press firmly for about 30 seconds, supporting the headliner from the bottom at the same time.

Example of 3M Dual Lock application; repeat for front edge of compass module:
99a0ce6fe08d71dad03a207664bd2009.jpg


Make sure you secure the new wiring harness to the existing one running up the driver side pillar with small wire tires.

In putting the visor hardware and A-pillar hardware back on exercise caution as you don’t want to pinch the pillar airbags. The pillar inserts forward end down first; make sure it seats properly, them pop the top in and insert the bolts. Also make sure the door gasket rubber doesn’t get hung up in the A-pillars.

AlfaOBD details next to turn everything on...


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Mpgrimm2

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^^^ FYI ... I now have the correct compass module connector and pins so future harnesses will not need the Delco pigtail spliced in!

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rangemaster728

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Let’s start with the compass programming.

Using AlfaOBD, save your configuration to Google Drive (you should be doing this anyway if you’re performing any work with AlfaOBD) ...look in the Log file and find Electronic Overhead Module (EOM) data; if it is not connected you’ll see something like this:

e5727a6c2679fc41c174b43e1faf53b3.jpg


This means the vehicle does not see the Compass Module; provided it is wired correctly (and you have a functioning compass module) we will enable that in AlfaOBD.

I advise you disconnect the negative side of the battery for at least 30 minutes prior to programming this one, as some have reported the standard “program a feature and turn the truck off for 5 minutes” doesn’t always work. If you’re doing the wiring harness and installing the compass module in the headliner this is a great time to do the battery disconnect.

This may have to do with the fact you’re going thru Canbus to program something on Linbus and the truck (after this 30-minute battery disconnection) effectively ‘takes inventory’ and will discover the compass module. I know I tried 3 times using the 5-minute downtime to get the Compass Module to be recognized and finally resorted to 30-minute battery disconnect and the programming finally took.

Turn the ignition to RUN (not ACC, as the Compass Module won’t be seen in ACC). You don’t have to start the engine.

Once connected to the vehicle on AlfaOBD go into the Body Computer and select the appropriate network; in my case it’s MY2020 PowerNet.
8f3068f9d2683101bcb01f05d6e173ee.jpg


Connect, then tap the Car Hood radio Button.
26509dcca0a884bf966a190653c2c6fb.jpg


Select procedure as “Car Configuration Change” (next to last item in the menu).
2779171ae6449b4ec2b67c3b214e041c.jpg



Next Select Option = LIN and Misc: Electronic Overhead Module (EOM) Present. Select value = Yes...then click Start, then Next. WAIT for confirmation of the change (this one takes a few seconds to confirm) then back out and terminate AlfaOBD, exit vehicle and wait at least 5 minutes.
36d01276e0ed7cd4b3d97e025ea17c03.jpg



Now that you’ve enabled the module you need to turn on three more items:

LIN and MISC: COMPASS MOUNTING ORIENTATION (0-360 deg); set to 0 degrees if you mounted the Compass Module in the same orientation as mentioned in the above posts. The field is blank by default so you must enter a number.
2f719309260d59ea7efa48baab89f26e.jpg


5 min delay, power down/exit vehicle.

VehConfig 3: DISPLAY COMPASS HEADING PRESENT = YES
5 min delay, power down/exit vehicle.
This ports compass info to the radio and EVIC.
de49ab6d6468ff7db857954f1e66830a.jpg


Cust.Set.Menu 1: COMPASS CALIBRATION CSM PRESENT = YES
5 min delay, power down/exit vehicle.

efdd89b30291f957aa26ef2cb3b30ac6.jpg




Cust.Set.Menu 1: COMPASS VARIANCE CSM PRESENT = YES
5 min delay, power down/exit vehicle.

These last two items can be confirmed after programming by going into the Setup menu on the radio...they should now show up on the radio screen.

Then take vehicle to a parking lot and perform a Compass Calibration (360 turn) with the Compass menu in Settings on the radio.

Note - The compass may be stuck on one heading until initial calibration is performed...mine was until it was calibrated.

Now - Set Compass Variance with the radio menu...the procedure is in the truck Owner’s Manual.

Also - If the radio menu compass items show up but the compass display on the radio says “No Signal”, and/or your EVIC shows “ - -“ for a compass heading (provided you have selected that in your EVIC menu), go back and save your truck configuration to Google drive again and check in the log/status file to confirm the truck discovered the compass module is actually present; if you’ve done this correctly you should now see something like this with actual compass data.
1aa011b98b39b025d0886a3f6e4c2a07.jpg




Dual mic programming post follows.


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rangemaster728

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Headliner dual mic programming.

Using AlfaOBD, connect to the vehicle and Body Computer and navigate to the settings using the “Car Hood” radio button.
9e1eae2529a8381515f69eca94ecd5aa.jpg

Now we set the mic parameters...as before, it’s best to set these one at a time, and do the 5-minute downtime/key out wait.

There are 3 parameters I changed; Microphone Configuration, Microphone Type and Microphone Tuning Parameter, all in the ECUConfig 3 section:
a9f151a3007f56f801834b6370141f65.jpg


First tell the truck how many mics you have (as mentioned before I put 2 Ram OEM mics in the headliner):
35cb85f516b99671d9872c55be657ecb.jpg

01084440e5b5680a3d917013e0f3e725.jpg

5 minute power off.

Next, change Microphone type (OEM headliner mics) to Type 2:

562bd6fe598f2e67eea527af0f55bc16.jpg

5 minute power off.

Finally, change the Microphone Tuning Parameter to Set 1:
2def5a605a0927d57feb1f8c13e07bbd.jpg


5 minute power off.

Your milage may vary regarding the microphone type and tuning set...these settings above just gave me the best results, but play with the Type and Tuning sets and make some hands-free calls to gauge the best audio response for you.

Ok...done for now.

MANY thanks to Mpgrimm2 of M2M Mods...his harness work is first-rate and we’ve had some discussions regarding this mod. If you are not comfortable in making up your own wiring harnesses and do not have the proper pins/sockets, crimp tools and/or pin extractors (in case you screw up) I cannot stress enough that you need to contact Mike and engage him in this work. He did a dual-display harness for me as well and the quality of his stuff is exceptional.


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tron67j

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If you're doing this as part of the installation of a overhead console where you didn't have one before, there is another DIY thread that talks about the installation process of the console but a lot of the postings are for pre 2018. Very helpful but I did find a couple variances in my installation. A couple things I found were that I did not have three wires going to my center dome light, there were only two. So where you usually only need to run an extra long wire to the passenger side C pillar for the map light I also had to run a wire to the c-pillar on the driver side to get the power when the lights stay on and then dim out after you leave the vehicle I also found a green connector right above the opening that I cut so I had to lift the tape and kind of slide it a little bit that it would move however I had to trim the tabs around the old temperature plug that is actually no longer used in newer 4th gen trucks and I also had to trim the tabs for what I believe is the rear window switch spot.
 

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View media item 30607
This is the connector that was over my opening. Not enough wire to move it out of the way so I trimmed some of the console insert as per above.
 
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