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Brake lights

I full time in a 2007 Dynasty Squire (side aisle) I Left the coach unattended for 7 days.  When I returned the brake lights were on and after stepping inside it was evident that mice had moved in in my absence.  Not sure if these are related but it is suspicious.

Checked my schematics and pulled the Brake fuse and relay in the RRB and the brake fuse in the FRB and the lights stayed on evidently being backfed by another circuit.  After touching the brake pedal with all fuses pulled the lights went out.  Re installed the fuses and relay and everything appeared to be working as it should.

Now on a trip and the brake lights again became stuck ON and this time I could not get them to go out by pulling fuses and stepping on brake pedal.  I don’t know what I did but they finally went out.  The turn signals and 4 way flashers cnmtinue3d to work OK. 

Am now parked near Vero Beach on the FL east coast and have spent most of today looking and searching.

  Noticed the ATC amber light was acting erratically.  Brake light fuse in FRB is now blown, may be what made the lights go out yesterday.  Decided to check the turn signals again and they worked for a while.  After more jiggling the turn signals and four way flashers don’t work either.  Checked fuses again and now the 30 amp fuse for the ABS system is blown.

Checked the schematics for interfaces with the ABS and brake light systems.  They do come together in connector 17 in the driver side console but I can see no damage. 

Also checked connector 141 as it is connected to the ATC switch, again no damage.  I checked the ATC switch and it appears to be working OK but am not sure of what the switch is supposed to do when momentarily activated.

Have looked in the steering column area for wire damage.  I have plenty of mouse evidence in the coach but none in the FRB, RRB, Driver side console or steering column.

I am out of ideas and now am ready to hire a qualified technician to trace the problem and or install new wires if necessary.  I still do not know if the mice and wiring problems are related.

Does anyone know of a good technician in the Florida area?

Thanks   John

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Good morning, JBB.  Some time back, I made a schematic in a format more readily understandable than what Monaco produced.  I'm attaching the one I made for the brake light system on our '06 Dynasty.  I suspect yours is very similar.  You will see one or more question marks on the drawing, and that's because the Monaco documentation that I had didn't give me what I needed to go further, and I didn't chase wires to ferret it out.  (Maybe I shouldn't use the word ferret, where you're dealing with your new rodent problem!!)

Looking at my drawing, though, the brake lights themselves are powered from the rear run box fuse.  The only "tie" to the front of the coach is the control for the K4 relay on board #2 in your rear run box.  Looking at my sketch, that control source comes thru that giant front run box connector J3, feeding from terminal TS1 (the fifth one, left to right) in the front run box.  But that said, If you pulled that rear run box fuse on board #2, you should have removed the ONLY source of power to the lights, themselves.  So even if K4 was "sticking" ON, with the fuse in the rear run box pulled, the lights should not have illuminated.

My drawing does not show the connections for the tow plug.  That least me to think that "Bliksem"'s lead is a good one.  That tow plug is one point where you could be getting a back-feed to the brake light circuit.

Hopefully my little sketch can be of help to you, or someone.  I'm looking forward to hearing what you find.  Hopefully the mice are innocent of any wiring damages in your coach!!!!  I've heard some horror stories, but hopefully you found out about them in time and can dispatch them before they hurt anything.  Cheers for now!

Schematic - Brake Lights.pdf

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Thank you.  I do not have a circuit board 16 in my FRB so my configuration is a little different than your 06.  

I have figured out that M is for cable connectors and J is for the five large round cable plugs in the FRB.  Have also figured out the circuit board numbering system.  I have not figured out the TS designation.  Based on your notes I assume the K designation is for the relays.  Are they 87 relays?

I am still confused as to how I am blowing the ABS fuses in addition to the brake and turn signal fuses.

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2007 Dynasty

My schematic shows the tow harness receptacle getting its signals directly from the steering column via a dashed line.  What is the significance of a dashed line on a Monaco schematic?

With fuses pulled I am getting 12V at the tow receptacle as I should.  I also read a direct ground on the left and right turn terminals with fuses pulled.  The receptacle has been potted at the factory so I assume the internal connections are still OK after working OK for 14 years. There is no sign of any physical damage to the receptacle.

I will check the steering column end for an unexpected ground both on the up and down stream ends of connector M-10.

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2007 Dynasty

Now I am confused.  At the first connector at the steering column the ohm meter shows no ground between the VIP smart wheel and the right and left turn wires.  It does show a ground on both left and right turn signal wires headed to the back of the coach and I thought I may find a damaged wire somewhere in the 45 feet from the front to the back of the coach.  

Opened connector M-112 in the engine bay and had a ground signal in both directions for both the right and left turn wires.

suggestions welcome.

I also have now lost power to my VORAD system.  The fuse in the FRB is OK

This all started with an unattended coach plugged into shore power except for the arrival of mice.

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I attached another of my sketches that shows, very basically, what the layout is in our front run box, and you are right, we don't have a board #16.  You are right about the cable designators and the J designation.  The TS stands for "Terminal Strip".  The one I referred to in my drawing is in the upper left corner of the inboard wall of the front run box.  I don't know if the relays are all alike, or not.  Actually, there are a number of them that are sized or shaped different from others.

I am not comfortable with calling a relay an "87 relay".  The 87 refers to the normally open (NO) contact.  Most, if not all, have one operating coil and one or more sets of contacts.  They may be SPST, SPDT, DPST or DPDT.  The first two are "single pole" (SP, used in a single circuit) and the second are "double pole" (DP, used in two circuits).  The single throw (ST) will be either a normally closed (NC) or normally open (NO).  The double throw (DT) will have a common contact that is tied to one or the other of the two remaining contacts.  All of that is determined by either the printed configuration on the relay or can be found by looking up the relay device number on the housing.  They are chosen in each case depending on the use for that particular circuit.  Terminal 30 is the common, 87 is the normally open terminal and 87a is the normally closed terminal.  Terminals 85 and 86 are typically the operating coil.  Polarity is not a factor, as a rule.

Your ABS experience is strange.  The interaction you are experiencing makes no sense.

My schematic shows the tow harness receptacle getting its signals directly from the steering column via a dashed line.  I suspect you may be looking at their drawing #3801001.  I've not assigned significance to the dotted line.  On my drawings, yes.  On Monaco's, I think they just use that as one of several line formats to make it easier to follow it on the drawing.  On mine, it shows the functional tie between the operating coil of a relay which may be somewhere else in a schematic than the contact(s).  Monaco is giving almost more of a wiring diagram than a schematic in that it keeps device geometry and relative location a factor on the drawing.  On my schematics, it is far easier to have the power supply bus at the top and the neutral bus at the bottom, and then to show all of the connections between the two on any part of any system.  In my sketch, the brake light relay coil is about mid-drawing, but the contacts in that relay are on the right side in the current path from the fuse, thru the contacts, to the lights and to the neutral. 

Looking at the first sketch I sent you, there are three sources for control power for the brake light system.  It can come from fuse #6 on either board #5 or board #6 as well as from fuse #1 on board #8.  Fuse #1 on board #8 is for control from the engine brake system.  Fuse #6 on board #5 is for control from the SmartWheel as it is involved with the turn signal functions.  And fuse #6 on board #6 is for control from the pressure switches on the brake system, itself.  But if fuse #3 on board #2 in the rear run box is pulled, on our coach, there is no way for the brake lights to come on unless the wiring has been compromised, somewhere.

I wish I was where you are, to be able to help.  But you've pretty much exhausted the information that I have available, particularly where our coaches aren't as close as I would have expected them to be.

I would not rule out the possibility that K4 on board #2 in the rear run box might be "sticking".  We had that happen on our coach when it was only about 3 years old, but in our case it was the tail lights that were staying on.  I wound up replacing the relay in the front run box to fix that problem.  I ordered the relay on-line using the part number imprinted on the relay.  I narrowed the problem to that device by waiting until the problem happened and then very gently tapped on that relay with the handle of a screwdriver, and sure enough, the lights went out.

Hang in there.  You'll get it solved, yet.  Also, if you want to pop me an email you can do that to k7jv@yahoo.com.  Good luck!

Layout - Front Run Panel (Front 3).pdf

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07 Dynasty Brake light up=date

Have NOT found any specific things to fix.  Removed the overhead panels in the basement looking for mouse problems and damaged wire looms.  Nothing suspicious.

Decided to replace the blown fuses in the FRB, 30 amp ABS, 15 amp brake and 15 amp flasher.  I never have determined what caused them to blow and was hesitant to replace them.

All fuses are holding OK.  Turn signals and 4 way flasher works OK.  Still had no brake lights.  Someone suggested I check the brake light switches on the front firewall.  The “normally closed” switches that disconnect the cruise etc. tested OK but the “normally open” switches did not appear to be working.  Later remembered that my air pressure was nearly at zero so fired up the coach. 

After getting air pressure the brake lights now work along with other light signals. 

I have not actually repaired anything.  The previous time I got things working without doing any “repairs” the brake lights got stuck on again.

All I know to do now is keep traveling and hope all is well.  Like walking on eggshells.

It will be another 10 days before I am on the road again to see what happens

Thanks to all who took the time to offer suggestions.

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