Author Topic: No brake lights  (Read 4149 times)

Robert Wagner

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No brake lights
« on: September 11, 2019, 05:55:36 PM »
Changed bulbs. Brakes lights do not work.  Signal lights do. Stuck in Missoula waiting for a fix. No one can find anything. Any ideas please

Stan Simpson

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Re: No brake lights
« Reply #1 on: September 11, 2019, 06:07:57 PM »
In the electric bay...the one under the driver's seat (outside) there should be a schematic on the inside of the door showing what each re-settable relay is for. The same schematic is also in the owner's manual. On our coach, the brake lights are K6 and CB18. I would check there for a bad breaker or loose connection.

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Mike Shumack

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Re: No brake lights
« Reply #2 on: September 11, 2019, 06:14:23 PM »
Maybe this diagram will help.


Robert Wagner

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Re: No brake lights
« Reply #3 on: September 11, 2019, 06:15:57 PM »
Ok this is Cheryl. Bobs sick. So I need step by step.  Guy here cannot figure it out. Standing in front of that bay. Have schematic and see no fuses

Robert Wagner

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Re: No brake lights
« Reply #4 on: September 11, 2019, 06:20:52 PM »
Can’t get that pdf

Mike Shumack

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Re: No brake lights
« Reply #5 on: September 11, 2019, 06:31:53 PM »
Will this work (jpg file)?

Robert Wagner

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Re: No brake lights
« Reply #6 on: September 11, 2019, 06:52:38 PM »
Two guys here can’t figure it out so far. Showed them your diagram

Robert Wagner

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Re: No brake lights
« Reply #7 on: September 11, 2019, 06:55:07 PM »
Ok they were working then tow vehicle had problems and now tow lightswork ontow car but now none on coach

Robert Wagner

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Re: No brake lights
« Reply #8 on: September 11, 2019, 07:02:33 PM »
Taillight converter for coach any in know where that is

Stan Simpson

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Re: No brake lights
« Reply #9 on: September 11, 2019, 07:03:32 PM »
They are not fuses. They are re-settable relays. They are behind the little double nuts. against the wall.

They look like this.... https://www.wiringproducts.com/10-amp-short-stop-auto-reset-circuit-breaker-12-volt.html

If you have to buy one they are available at most auto parts stores, very in-expensive. Caution: Make sure it has no brackets like the one in the picture. If it has mounting brackets, it will not fit in your coach. It just has to have the two studs as shown.

Stan Simpson & Becky Glover & Moe the cat
2005 Monterey Laguna IV
C9 400 Cat
Honda CRV toad

Robert Wagner

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Re: No brake lights
« Reply #10 on: September 11, 2019, 07:07:47 PM »
Where is that in the coach

Robert Wagner

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Re: No brake lights
« Reply #11 on: September 11, 2019, 07:17:30 PM »
They said that’s not it. Still no brake lights. 😖😖😖

Mike Shumack

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Re: No brake lights
« Reply #12 on: September 11, 2019, 07:54:47 PM »
Bob, did the mechanic/helper check for 12V power at the "K25 Relay" (note that it may be a different # relay,so confirm by looking at the relay location diagram on the bay door) when the brake pedal is depressed? That is an easy place to get to to start the troubleshooting.

If you have power at the K25 relay (the terminal 85) then you know the power is getting through the brake light switch.

For troubleshooting, you want to split the circuit your testing into sections (so split to half before the relay, and the half after the relay to the lights). Now if you have power at the relay terminal 85 you know everything from the battery, through the brake light switch to that relay is good. Then you would know the problem is from the relay to the brake lights (and don't forget to check the relay it self). If no power is at terminal 85 then you make your next check for power at the brake light switch. or connector C6-16 (if you find it).

At least that's the way I would proceed.

Steve Huber Co-Admin

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Re: No brake lights
« Reply #13 on: September 11, 2019, 08:47:23 PM »
Updating Mike's info based on a 2006 Monterey Elec Bay Diagram.

The Thermal circuit breaker is CB7. It powers both the Brake and Parking lights. So if you have parking lights, CB7 is OK.

The Brake Light relay is K18.

Brake light signal to lights is connected to TB1 post 8. If 12V there when pressing on brake pedal, problem is at rear of coach. Look for blown fuse or burned connections in wires leading to brake lights as it sounds like circuit was overloaded when working on tow car. (I'm assuming tow car is disconnected from coach now).

If there is no voltage on TB1-8, the problem is probably K18. Replace it.

Steve


Steve
2015-          07 Contessa Bayshore C9,  400 hp
2013-2015: 00 Marquis Tourmaline, C12, 425 hp
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Robert Wagner

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Re: No brake lights
« Reply #14 on: September 11, 2019, 09:26:02 PM »
Ok here is what it was. A line in the electrical bay for the tow car that was installed for brake system somehow got disconnected and was shorting everything out. It was hidden in behind a bundle of wires. Just sitting there barely connected. Go figure.


Thank you everyone so very very much.

Cheryl