06 Monterey - No Headlights

[Paul Haaf]

Does anyone have a schematic of the headlight circuit? I have an original book but there is nothing on the headlights!
I have spent a few hours troubleshooting my headlights which stopped working all together. Both low and high right and left are out. Signal lights and marker lights are fine.
I don't get a high beam indicator on the dash when operating the switch on the steering wheel.

I checked the electrical bay and have power on Headlight Battery and Headlight Ign wires. That voltage is on the dashboard switch and all controls work there including the instrument dimmer.
When the switch is pulled voltage goes out Headlights 72. That wire goes to a bundle and maybe back out to the electrical bay. I also checked the connectors from the steering column and they look good, they go into the same bundle.

At the headlights I have a 5 wire harness broken out to three cables. Headlights on three conductors, marker and turn signals each on a two conductor. So one conductor must be ground for all bulbs since the other two functions work.

Would there be another relay or splice that I am missing here?  I have seen the fix for dim lights by adding relays posted on the forum. I don't think that was done to this coach, if it was where would the relays typically be mounted? The electrical bay seems to match the diagram i have and no spare relays are in there.

Any help would be appreciated!

[Eric Maclean]

Paul
If your coach has the old style push pull head light switch on the dash the first place to check is that switch .
They are an old style Ford head light switch that has a circuit breaker built into it which are known to get weak and go bad and the result is everything works fine except the head lights .
Usually they will work for a short period and then shut off until they cool down again and come back on but they don't always fail that way.

When you speak about steering wheel switches you are talking about a smart wheel setup where you're cruise control and headlight dimer switches are located.
The coach assist library has a trouble shooting manual for the smart wheel system along with operation and wiring diagrams to help diagnose it's operation.


Hope this helps
Eric

[Joel Ashley]

BCS did our headlight modification years ago.  Reckon I was too busy or too lazy to do it myself, and their experience made it a quick job with minimal labor cost.  We were in for other servicing and it was a simple add-on.

Joel

This is where they mounted the relays:

[Paul Haaf]

Thanks Eric, I did locate the info on the Smart wheel, I have a different model so the jumpers didn't match. I did locate the module and identified three wires labeled for headlights. a Batt one with 12vdc then headlight one and a headlight out. I don't see any voltage on the out wire and when I disconnected and jumped 12vdc to it I heard a relay clicking, sure enough there is a relay in the electrical bay not shown on the bay schematic with a headlight wire on it. The jumper did not get the lights on so I still have more troubleshooting to do. I might need my co-pilot to help now!
I am considering that it could be a bad VIP module. Listed as VIP Control Module Series II SM211 RevB BIO339C
Any idea of a source?

[Paul Haaf]

Hi Joel, I don't have those relays, but I do have one in the bottom row that was not on the schematic. My VIP Module is in the lower right corner of the electrical bay.
I plan to troubleshoot more tomorrow.

Thanks for the reply!

[Joel Ashley]

Check your VIP module’s connector pins for green corrosion, and if possible to open it, check circuit boards inside.  Page 4 of the wiring diagram shows the module design;  I’m assuming from your posts that you have that, otherwise check Coach Assist for mine, or I can post the page here.  Also make sure all ground buss screws are snug (2 busses lower left, under the relays).

I’m certainly not an expert, but I’m not convinced it’s your VIP that’s the issue.

-Joel

Out of stock here, but they may provide guidance. 
https://www.nwrvsupply.com/product/vip-smartwheel-control-module-series-ii-sm211-in-stock/

-and-
https://www.nwrvsupply.com/wp-content/uploads/2022/08/sm211-Information.pdf

[Steve Huber Co-Admin]

Paul,
12v for the headlights originates at the headlight thermal circuit breaker on one of the bus bars in the front elec bay. It then runs through the headlight switch and back down to the headlight high and low beam terminal posts in the front electrical bay (TB4 & 5 if I remember correctly). From there it runs to the headlights. The dim headlight mod, if you have it, was installed between the switch and TB 4&5.
Steve

[Paul Haaf]

Joel, that link is very helpful. That matches my unit and has the schematic I needed.

Steve, I will check out TB3&4 and see what I find. It seems the only way to switch high beam is via the steering wheel. I have attached a snip from the VIP manual.

It is getting closer to making sense. Not sure where the power resister is that they indicate on high beams...

Thanks again for the help!

[Eric Maclean]

Paul
The vip trouble shooting and wiring diagrams are in the coach assist section of the forum
You may get more out of the troubleshooting section .

[Eric Maclean]

Paul
On the VIP 211 wiring diagram it appears that the head light power source enters the Vip Module on connector P2 at the centre terminal #5 and is switched via the module and exits via terminal #6 in the P2 connector.
From there the diagram shows the dimmer switch as a separate switch likely a mechanical switch on the left side steering column stock.
Is yours this way or does your have the hi/ low switching on the steering wheel pad?

The power resistor you are looking at is to drop the voltage to the high beams for day time running lights it is feed from terminal #11 in the P2 connector and the high beams should be lit with the ignition on and the parking brake released.
When the VIP module receives a head light on command it switches two internal relays one for the marker lamps and the other for the head lamps , the head lamp power is then feed through the dimmer switch and if on high beam bypasses the power resistor providing full power to the high beams.
It is worth mentioning that the marker and head lights use separate relays within the module which would lead you to believe if the marker lights work and the head lights don't you should check for power into terminal #5 and out at terminal #6 if you have power in and out then you need to check the wiring beyond the module going to and through the dimmer switch.

Hope this helps
Eric

[Paul Haaf]

Eric, thank you for the suggestions. It is a very rainy day in Connecticut today so I just got a chance to check a few things, with some help from my wife.
I was not thinking properly about basic operations. I forgot the high beam is only triggered by the turn signal stalk! The buttons on the steering wheel are as you pointed out Marker lights and Headlights. High beams are now working when we switch the dash main headlight dimmer switch and activate the turn signal high beam. I do not get any low beams, I did verify the VIP module triggers and there is a relay that puts out +12vdc in the electrical bay on the NC terminal. That went active if I hit the steering wheel trigger or when I pull the headlight dimmer switch.
Trying to wrap my brain around the high beams connecting to the dimmer circuit. I don't recall ever seeing daytime running lights, but never really paid that much attention. Is that an option or would it be standard for 2006?

Water started dripping into the electrical bay so I closed shop for the night!
I will pick it up again tomorrow, I might check voltage at the headlight plug, it would be crazy if both low beams are blown, I replaced both assemblies two years ago. This is the first trouble since then.

This has been a fun one!

[Eric Maclean]

Paul
Here in Canada day time running lights have been mandatory for at least 25 years but where you are it was not so it is quite possible that your coach was built without DRL.

if you have low beam operation then you are getting power through the VIP module and that means the steering wheel switches are working ok and the module is doing it's job . It also means there is power getting to and through the dimmer switch at least on the low beam side of you aren't getting high beams now the problem is either at the dimmer switch itself or the wiring beyond it.

Hope this helps
Your getting there
Eric

[Paul Haaf]

I found the elusive bugger!
It was the connector in the electrical bay where it meets the harness to go out to the front cap.
When I pushed up on the lo beam wire the connection was made again. I will take it apart and clean the connectors.

No DRL on this coach. The marker lights come on with the first stop of the Headlight pull switch and the headlights come on with at the second stop.

I have attached a picture of the terminal and connector...

[Joel Ashley]

Good deal!  I’ve found those cylindrical connectors a problem for corrosion myself, that very one I believe.

To clean the pins, a kit similar to this can be handy: 
https://www.amazon.com/Innovative-Products-8042-Connector-Cleaner/dp/B007WQQKTU/ref=pd_lpo_sccl_2/147-7146796-1630227?pd_rd_w=DKHM5&content-id=amzn1.sym.116f529c-aa4d-4763-b2b6-4d614ec7dc00&pf_rd_p=116f529c-aa4d-4763-b2b6-4d614ec7dc00&pf_rd_r=B5H25MX893GHTKJ650J6&pd_rd_wg=9QCZM&pd_rd_r=068f71b5-9316-493e-bfd2-fd9c788c763f&pd_rd_i=B007WQQKTU&psc=1

There are plenty of other kits available and I’d prefer brushes over files, so shop them a bit, but also finish off the job at hand with DeOxit, and CorrosionX.  I keep an arsenal on hand, but the Terminal Cleaner Kit shown below is for larger trailer-type devices;  I’ve been using small wire brushes, but will be getting a kit sized for smaller tubes/pins.

Joel

[Paul Haaf]

Thanks for the suggestion Joel. I will check that out. I did just order a crimp tool. in the process of troubleshooting the headlights I lost the bay unlock function. It turned out to be a loose common crimp on the relay right above where I found the headlight relay. I had to replace the crimp end and the tool worked great.