MX 7000 HELP

SFD36USMC

Member
Sep 7, 2010
27
I just bought a used light bar from a buddy of mine. 48" MX 7000. Five rotators. Intersection, alleys, takedowns, and flashers along with an arrowstick. I bought it home and attempted to test it by grounding it and touching the paired color wires to the battery. Note: all the halogen bulbs appear to be good. Here are the issues:


1) Left Alley and flashers work fine.


2) Center rotator does not rotate or illuminate.


3) Other four rotate but only the extreme right rotator bulb illuminates. The other three illuminate but they are very very dim.


4) Take downs and intersections do not function.


5) Right alley does not illuminate.


Where would you start? Also note, the light bar is in excellent condition.


Thanks so much for taking the time to help out with this.


Drew
 
May 21, 2010
1,591
Berlin, MI, 48002
It might be a ground, or there could be wires up inside the bar that are smashed between other metal parts like under the black rotator decks. I would start with the ground & go from there. If its' not that, I'd take the lenses off, then the decks & check the wiring out inside the bar.
 

shues

Lifetime VIP Donor
May 21, 2010
10,276
NW Indiana
This could happen if you main ground wire is loose, is broken, or is completely disconnected from the frame.


You can quickly test the theory that there is a bad ground by attaching a temporary ground wire to one of the four bolts that hold on either of the two mounting feet. These bolts attach directly to the frame, and are a great place to connect a ground wire for testing.
 

EVModules

Member
May 16, 2010
864
Deer Park, WA
SFD36USMC,


I decided to post your PM response in order to let others in on the topic if you don't mind...


You'd need to take off the lenses and detach all of the middle decks so you can inspect all the wiring. Focus on the rotator motors at this point and not the bulbs for now. Chances are you may have some bulbs that are burned out. I can already tell that you have a ground issue when you mentioned dim bulbs. When there are dim bulbs, it's finding ground through other components that also includes bulbs.


The decks are grounded by their own fasteners to the frame so testing it with the decks apart just won't make it work. You can use a temporary jumper or simply touch the deck to the frame for a quick test. You won't harm it with this method. Just keep clear of the rotators.


Ensure that the lightbar's black ground cable is connected securely.


Check each wire and verify that it's connected securely to the lighthead(s). Are they factory wiring? If not, you'd need to inspect closer.


When you get everything to work, double check the suspect bulbs by inspecting the base. A batch of bad bulbs caused the tip to melt, shorting it to the ground. If that's good, swap places with a good bulb, this will tell you very quickly of it's a bad bulb. If the problem exist at the same place, you'd need to double check the base. It should move freely in the housing to provide a solid contact.


Check the rotators, it should have absolutely no contact with any part of the deck, wiring, etc. It's not uncommon for folks to blame rotators when there isn't sufficient power. They use a lot of juice, hook it up directly to a good battery for testing. Rotators need a minimum of 14 gauge, each lamp 16 gauge. Pairs of rotators on one wire should be 12 gauge.


Original factory wiring for the intersectors, especially smart intersectors are inadequate and require bumping up a wire size.


When replacing wiring, do follow the existing harness especially to the decks as it should be only one bundle of wiring to facilitate ease of servicing (service slack). When reseating the decks, take care not to pinch any wires. Half of the problem can be traced to pinched wiring.


Replace any "browned" connectors, it's a sign of overheating and will fail. Install new quick-disconnect connector(s) at one or both ends if you can't find a mating piece. It's a good idea to use dielectric grease on the connectors, a little dab before pushing the connectors together will go a long way.


When all's done, tell your buddy he owes you a six pack for the trouble!
 

SFD36USMC

Member
Sep 7, 2010
27
That could be it. I will check with I get back from my classes later. I didn't have it attached well. Would that cause light to not function at all, though?


And does anyone know what color wires control each device, or is that a crap shoot?


Also, does anyone know where i can find the plastic plug that plugs into the back of the Code 3 Arrowstick controller?


-Drew
 

SFD36USMC

Member
Sep 7, 2010
27
Status update. I figured out the issue (I won't say what it was, because it was pretty stupid). But the light bar is now functioning but still with a few things I have yet to figure out:


1) The center rotator still does not rotate.


2) The outer two rotators are fast rotators. But now when all four rotate, the outer rotators are now rotating slow, even tho they are fast rotators, and the bulbs have dimmed. When I originally tried the bar, only the outer two illuminated and the bulbs were much brighter then they are now with all 4 rotating.


I took a multimeter and did not see any power going to the center rotator. There is a blue wire with a connector on in which lays below the center rotator which is getting power. So i hooked that up to the center rotator, but it still does not function.


Any suggestions, besides get an LED bar ;) I have something for rotator bars.


Thanks again guys and gals.


Drew
 

SFD36USMC

Member
Sep 7, 2010
27
Yeah, there was a ground issue before which caused only the outboard rotators to rotate. When that occured, they spun fast and bright. After figuring out the ground problem, all four rotate, but the outboard roators (highspeed) now spin slow like the inboard two and all are not as bright as they should be...
 

EVModules

Member
May 16, 2010
864
Deer Park, WA
You're still having ground issues. Try taking a bare thick wire and touch it between the base of the lightbar at a different location or at the power source and the other to the base of the rotator. If it improves, the deck is not quite tight to the base. Was it screwed down securely when testing?
 

SFD36USMC

Member
Sep 7, 2010
27
No, the lightbar isn't on the truck yet. It is just on my work bench, since I am testing it. I had the thick ground wire attached to a bolt on the outside wall of my engine compartment. That ground is good.


And I did have it powered by the battery with the truck running...
 

Jarred J.

Lifetime VIP Donor
May 21, 2010
11,580
Shelbyville, TN
ok in relation to your "bench" and the trucks battery, what are you using to connect them? Jumper cables?
 

SFD36USMC

Member
Sep 7, 2010
27
The bench is by the garage door, so the ground is connected to the vehicle body and the power cables are connected right to the battery.

elbnodeletebutton.PNG
 

kadetklapp

Member
May 21, 2010
1,568
Indiana
Ground the cable to the battery for now. It sounds like you have some internal ground issues. The rotator decks are mounted to small brackets. Make sure the brackets are tight into the frame of the bar.


You could also be pinching some wires under those rotator decks causing a short.
 

SFD36USMC

Member
Sep 7, 2010
27
Hey gents,


Everything now works fine on the bar, except for the center rotator. I think the motor may be shot. Thanks for all your help. Half the battle is done. Now i just have to get myself to drill into my 2010 Ram 2500....not too excited about that :/


drew
 

SFD36USMC

Member
Sep 7, 2010
27
Connecting the right wires, mostly. That, and I think there were some wires up against the deck. I took the decks off and "re-packed the wires, and it works. I still have an issue with the center rotator, which, I'm thinking the motor is out.


There are a set of blue wires in the wiring harness that seem to do nothing. I'm wondering what they are for, since everything else works. Any ideas?
 

shues

Lifetime VIP Donor
May 21, 2010
10,276
NW Indiana
In an all-light MX7000, the center rotator is usually powered by one blue wire, and the other blue wire is usually spare.
 

SFD36USMC

Member
Sep 7, 2010
27
Nothing happens when current is applied to the blue wire. Also, one of the white wires creates a "clicking" sound in the bar, but doesnt activate anything. It sounds like the same "clicking" the flashers make, but it only does it once, and nothing turns on. Any ideas on that? (Take downs and flashers function)


Drew
 

shues

Lifetime VIP Donor
May 21, 2010
10,276
NW Indiana
Unbolt the center deck, disconnect the center rotator, making note of which color wire it was connected to, and see if the center rotator works when bench tested by itself. If it works on the bench, then there is a break in the circuit somewhere. The best way to find out what the white wire does is to unbolt the decks and trace it by hand. I have seen white wires used for takedowns, work lights, flashers, etc.
 

SFD36USMC

Member
Sep 7, 2010
27
I'm not by the bar right now, but I recall the center rotator being a red wire. All 5 rotators are on a red wire. I'll bench test the rotator this afternoon....What is the going rate for a used rotator assemply if i need one?
 

shues

Lifetime VIP Donor
May 21, 2010
10,276
NW Indiana
You should be able to get a used MX7000 rotator for around $10-$20, or a used Excalibur rotator for around $15-$25 on this board.
 

shues

Lifetime VIP Donor
May 21, 2010
10,276
NW Indiana
Excalibur rotators are directly interchangeable with MX7000 rotators, and vice-versa. The main difference is that the Excalibur rotators have plastic reflectors while the MX7000 rotators have metal reflectors.
 

SFD36USMC

Member
Sep 7, 2010
27
That's awesome to know. Thanks.


I know i posted it elsewhere, but I am also looking for the following items:


(2) Amber outboard domes


(2) Amber flasher filters


(1) High Speed rotator assembly


(1) Green 7 pin connector for Code 3 Arrowstick Controller


(1) 6 switch lightbar controller.


If you have any, PM me with a total price including shipping and we'll work it out.


~D
 
May 21, 2010
148
Corbin, Kentucky
SFD36USMC from past exp. with Mx lightbars its worth the extra effort to install a few relays to run the lights, makes for brighter, faster running rotators under load.
 

rwo978

Member
May 21, 2010
5,196
ND, USA
SFD36USMC said:
I'm not by the bar right now, but I recall the center rotator being a red wire. All 5 rotators are on a red wire. I'll bench test the rotator this afternoon....What is the going rate for a used rotator assemply if i need one?

If all 5 rotators are on one red wire, it's been re-wired. Is the harness factory? If so, it should have 2 red, 2 orange, 2 white, 2 yellow, and 2 blue, and the 1 black ground. The reds are for rotators, paired per wire (inner and outer). White is normally for TD, Orange for flasher, and yellow for alleys. The blue go to the center of the bar. There should be and extra blue, white, and orange.


If it is the factory harness, you're going to burn up that one red wire running 5 rotators on it. It's not large enough to handle that load.
 

SFD36USMC

Member
Sep 7, 2010
27
Sorry it's been awhile since my last posting. The camouflage job keeps me at bay from the computer at times. Benching testing the motor didn't work. I got a fast rotator from someone on this site in the the mail today and "voila", works excellent.


I polished up the lenses with some plastic polish, and wow, did that make a huge difference.


A few more questions for the peanut gallery out there:


1) How would you go about mounting it on a 2010 Ram 2500 Crew Cab? I'm debating 2 things. Just drilling and installing the bar via the 4 mounting feet near the back 1/4 of the roof, or possibly buying a BackRack and putting it on there.


2) I'm lost on how I can mount the 6 switch controller, arrowstik controller, and CB in the space below.


Again, thanks for your input...


Drew

photo 1.JPG
 

Alovebaby41

Member
May 23, 2010
354
Texas
Something that you could be running into is that maybe you aren't putting the center rotator power wire to power i know on my mx it has a separate wiring for stage 1,2,3 so maybe just a thought to think about.
 

TCO

Member
May 21, 2010
808
Malvern,Pa
dont ruin a new truck by drilling into it,spend the extra $150 and buy a back rack and mount the bar to that and run the cable down the rack and up into the truck via the access port in the wire channel under the door sill or in the back wall of the truck.
 

SFD36USMC

Member
Sep 7, 2010
27
Thanks TCO. I don't know enough about wiring this shit up, so I'll have to look for that access point. Thats my biggest issue, not screwing too much shit up or drilling. I'm looking at the best place to mount the switch boxes and run the wires up into the cab...Any suggestionss?


D
 

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