2016 Forester MBS 2401s - LED Brake Light Will Not Turn Off

dukeboone · 10-01-2015, 09:40 PM

Yes, that's correct. The vehicle is parked, the house batteries are off and the left tail light is still illuminated. Furthermore, none of the running lights work other than the headlights. Interestingly they all worked when I left the dealer yesterday and now that I have driven the 400 miles home it seems there's some sort of short. Any ideas Josh or Brian? I suppose the LED's won't draw much overnight but I'm not sure what else I can do tonight.

dukeboone · 10-01-2015, 10:32 PM

If I disconnect the vehicle battery for a few minutes and plug it back in, all the running lights come on (running light/headlight switch off). Then after a few minutes it all goes back to no running lights and only a right brake light and right turn signal. Left brake running light is dimly lit and will not at that point go out. Left turn signal does not work and left brake light does not work. It all worked 400 miles ago.

vwexpert · 10-01-2015, 11:06 PM

dukeboone ...what was done to coach at dealer? Double check what they did. There might be a bulb in wrong / or wrong bulb in socket / loose connection at one of the bulbs and it's causing a feedback. When all the lights are on is there a light that is dimmer than the rest?
Jim

dukeboone · 10-01-2015, 11:19 PM

Hey Jim - Thanks for the reply. Interesting that you were the first to respond since I do believe you also picked up your 3011 recently from the same dealer. Not that I'm trying to infer that any of this is dealer related. Anyway, they didn't do anything to the coach that I'm aware of other than maybe some inspection(s) and post delivery washing. By the time I was all done with my PDI yesterday we headed to Reno, NV for the "out of state" delivery and by the time that was all said and done it was dark and I'm 100% confident that all of the running lights worked properly. I can't say the same for the left brake/running light because I didn't check it. I do know that it didn't remain on. Anyway, I removed the LED plate from the rear of the coach and each "light" is basically a "motherboard" of LEDs and no sockets.

The left brake/running/turn is dimmer than the rest after the battery disconnect/reconnect that seems to get the other running lights going. When it's just the phantom left brake/running/turn when everything else is off, it's super dim.

My guess is that there's some sort of short with one of the "motherboards" or plates of LEDs. It wouldn't take much to illuminate the LEDs ever so slightly, and the short is maybe not letting the power to get through to the rest of the running lights. Still wouldn't explain though that I can get them all working after disconnecting the coach battery for a few minutes and reconnecting.

Thanks for your help. Let me know if you have any other thoughts.

**RedLdr1** · 10-02-2015, 09:14 AM

I suspect you have a issue with a controller board feeding the lights rather than an individual light. If you disconnect the left tail light module does everything then work correctly?

dukeboone · 10-02-2015, 09:52 AM

Quote:

Originally Posted by RedLdr1

I suspect you have a issue with a controller board feeding the lights rather than an individual light. If you disconnect the left tail light module does everything then work correctly?

Thanks. I'm going to disconnect the light this morning and see if that helps. The controller board, that sounds like a MBS item. Or is my interpretation in correct? Thanks!

dukeboone · 10-02-2015, 10:17 AM

Update. Everything appears to work normally with left tail light assembly removed.

**RedLdr1** · 10-02-2015, 01:10 PM

Quote:

Originally Posted by dukeboone

Update. Everything appears to work normally with left tail light assembly removed.

Okay... Now swap it with the good right side tail light and see if the problem reappears. If it does reappear on the left side you have a controller module, or wiring, issue. That is a FR part by the way.. If it does not reappear on the left and the right side now acts up you most likely have a lamp assembly problem.

A32Deuce · 10-02-2015, 01:17 PM

The problem appears to be that tail light. Either the wiring that feeds it or the tail light itself. I lean towards a short /cross in wiring to that light. Check the wires not connected to the light with a volt meter, then connected to light. Or like others my say, Take back to dealer, warranty fix.

dukeboone · 10-02-2015, 01:21 PM

I removed the left tail light and tested it at my local independent RV shop. The light module seems to work fine. I reconnected everything and all was well. However after a period of time it reverts back to glowing really low with everything off and not working properly. If I disconnect the coach battery for a while and then reconnect I can get everything to work for a while and then it reverts back to being finicky. I'm thinking there's a poor ground connection somewhere. Thoughts?

Cfritts · 10-02-2015, 01:47 PM

This is a common problem and has been discussed before. Ours did the same thing. It was on for a couple of weeks. Right before we took it to the dealer is stopped doing it and it has worked properly since. I read via the board here that it was due to the computer panel for the lights being mounted out in the elements (under rig but no cover) and that is the cause.

I refuse to try and trouble shoot myself on a brand new vehicle that cost in the $80,000 range. It should be warranty and repair places should get paid to trouble shoot it.

Just my thought.

A32Deuce · 10-02-2015, 02:24 PM

Try post #9.

dukeboone · 10-02-2015, 03:27 PM

Thank you everyone for your help. It's Friday afternoon, so not going approach my local dealer quite yet. I'll probably resort to that on Monday. Hope that goes well, there's a few reasons I didn't purchase from them, the $40k price difference was only one. Meanwhile I'll probably try #9 and if Brian or Josh see this, let me know where this computer panel is located. Drove through quite a rainstorm getting this thing home and wouldn't be surprised if the exposed panel is part of the problem.

vwexpert · 10-02-2015, 03:34 PM

It does seem like a moisture related issue. Try to locate the control box and spray a lot of WD40 on / in it if possible. I would call Nate or Kevin and ask them where the controller is.

A32Deuce · 10-02-2015, 04:12 PM

dukeboone, you can use a volt meter and check with house bats on/off. That should narrow down where the problem is.

A32Deuce · 10-02-2015, 04:15 PM

I look at it this way, if you have an idea what/where the problem is helps not to get taken. You don't have to be the one to fix, but if you know, goes a long way.

kysunseekermbs · 10-02-2015, 06:16 PM

I have had my 2016 Sunseeker mbs 2400w for 1000 miles and one tail light just came on and I can't get it to turn off. I have been driving in the rain so I suspect a water related issue. I will try some of the things mentioned here. It sounds like it may go away when it dries out.

dukeboone · 10-02-2015, 08:06 PM

Interesting report kysunseekermbs, sounds like you're experiencing the exact same thing as me. I did find two grey connectors, a relay and something that appears to be associated with trailer wiring. I unplugged the two gray plugs, one of which had no gasket and both had considerable amount of moisture inside, to the point of dripping out of the connector interior. The RV is in my garage so I'm leaving them unplugged for now to dry out. So far it doesn't appear to have solved the problem although the phantom light is much brighter now.

dukeboone · 10-02-2015, 08:08 PM

Not sure if this photo will show up or now, using the mobile app...

A32Deuce · 10-02-2015, 08:59 PM

You can get a product from CRC that you spray into the connection and displaces the water. Electrically safe. Then I would put dielectric grease in the connection and prevent further problems. I use it for connections that are exposed to weather. Electric Companys use it for same reason.

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