Author Topic: Brake lights stay on  (Read 7628 times)

Offline lostagain

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Re: Brake lights stay on
« Reply #15 on: November 18, 2020, 07:00:48 AM »
If you don't have them already, you need the wiring diagrams for your bus. You could then follow the circuits connection by connection to find your problem.

Also, a transmission brake is a retarder. Jacobs are in the engine heads.
JC
Blackie AB
1977 MC5C, 6V92/HT740 (sold)
2007 Country Coach Magna, Cummins ISX (sold)

Offline Mozz1k

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Re: Brake lights stay on
« Reply #16 on: November 18, 2020, 08:29:32 AM »
Are the wiring diagrams hard to find?

Offline richard5933

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Re: Brake lights stay on
« Reply #17 on: November 18, 2020, 08:38:08 AM »
Have you tried to pull the fuse for the brake light circuit? If you have a short somewhere feeding the system, pulling the fuse on the circuit that is supposed to power them would let you know. If you pull the fuse and they go off, then they are not getting back fed from another circuit.
Richard
1974 GMC P8M4108a-125 Custom Coach "Land Cruiser" (Sold)
1964 GM PD4106-2412 (Former Bus)
1994 Airstream Excella 25-ft w/ 1999 Suburban 2500
Located in beautiful Wisconsin

Offline lostagain

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Re: Brake lights stay on
« Reply #18 on: November 18, 2020, 08:47:22 AM »
Call Prevost. They will get you the wiring diagrams, or any manuals. They will ask for you VIN.
JC
Blackie AB
1977 MC5C, 6V92/HT740 (sold)
2007 Country Coach Magna, Cummins ISX (sold)

Offline buswarrior

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Re: Brake lights stay on
« Reply #19 on: November 18, 2020, 12:20:03 PM »
If you farm out this work, be prepared to have your wallet emptied while someone else teaches themselves about your bus... if auto techs were any good at electricity, they would have become better paying electricians...

Better to suck it up and teach yourself, this is only the beginning of needing electrical investigative skills...

Not fun, either way...

Happy coaching!
Buswarrior
Frozen North, Greater Toronto Area
new project: 1995 MCI 102D3, Cat 3176b, Eaton Autoshift

Offline freds

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Re: Brake lights stay on
« Reply #20 on: November 18, 2020, 09:51:39 PM »
If you farm out this work, be prepared to have your wallet emptied while someone else teaches themselves about your bus... if auto techs were any good at electricity, they would have become better paying electricians...

Better to suck it up and teach yourself, this is only the beginning of needing electrical investigative skills...

Not fun, either way...

Happy coaching!
Buswarrior

LOL a little kernel of truth. It's not like you have to learn digital electronics. Just get on YouTube and watch basic electricity videos until it sinks in via osmosis. If you need an advanced degree buy a cattle prod WEG!!!

Ok I have had a few this evening!!!


Offline luvrbus

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Re: Brake lights stay on
« Reply #21 on: November 19, 2020, 03:19:56 AM »
Call Prevost with the serial numbers yours may have the chassis computer (CAN System) and the average person can do a lot of head scratching for days when all it needs is a re-boot
Life is short drink the good wine first

Offline windtrader

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Re: Brake lights stay on
« Reply #22 on: November 19, 2020, 04:24:53 PM »
It is necessary to learn the basics but sometimes reinforcing what you read and learn and what happens when probing around the bus is so much harder. Can be deathly frustrating due to all the hands on wiring over the decades and screwing around with tapping with different color wire, rerouting wire around something not working, basic wires having internal breaks, etrc, x 1000.
Even with very solid understanding and experience, electrical gremlins can hurt the best of us.
Don F
1976 MCI/TMC MC-8 #1286
Fully converted
Bought 2017

Offline Jim Eh.

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Re: Brake lights stay on
« Reply #23 on: November 22, 2020, 07:50:33 AM »
BTW,  brake lights will be on if Jake/retarded are switched on

Not on older units. There is a company manufacturing a kit to update your lighting system to make that happen tho. I guess if you are doing a bunch of mountain driving, it would be a good update.
joshenginebrakelight.ca
"Some days it's just not worth chewing through the restraints"
Jim Eh.
1996 MC12
6V92TA / HT741D
Winnipeg, MB.

Offline buswarrior

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Re: Brake lights stay on
« Reply #24 on: November 22, 2020, 07:58:37 AM »
Ask yourself

I am jaking down the mountain, and 'round the bend, the traffic is stopped...

What does the rear of my coach look like to those following, when i have to go deep into the brake pedal?

If the brake lights are already illuminated for the last few miles...?

If you'd like to do something modern, add the amber lights up high that New Jersey transit has been using for decades now, and the Vanhool megabus double deckers too.

Solid amber when a retarder or jake is engaged, leaving the brake lights to indicate the brakes are being applied.

It's your bus, you don't have to compromise.

Happy coaching!
Buswarrior
Frozen North, Greater Toronto Area
new project: 1995 MCI 102D3, Cat 3176b, Eaton Autoshift

Offline chessie4905

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Re: Brake lights stay on
« Reply #25 on: November 22, 2020, 08:05:46 AM »
But... If following vehicle doesn't know what those other lights mean.
GMC h8h 649#028 (4905)
Pennsylvania-central

Offline buswarrior

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Re: Brake lights stay on
« Reply #26 on: November 22, 2020, 08:10:07 AM »
It doesn't really matter if they don't know what the amber lights mean, the change in state is not nearly as accident triggering as the alternative?

About the only person on here that can dramatically slow their coach with the jakes is Cliff, with his ISX, just about all the rest of us, the retarder/jakes just drag, and don't represent the threat to following traffic.

Happy coaching!
Buswarrior
Frozen North, Greater Toronto Area
new project: 1995 MCI 102D3, Cat 3176b, Eaton Autoshift

Offline chessie4905

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Re: Brake lights stay on
« Reply #27 on: November 22, 2020, 08:12:50 AM »
Isn't going to help idiots that don't allow proper following distance.
GMC h8h 649#028 (4905)
Pennsylvania-central

Offline windtrader

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Re: Brake lights stay on
« Reply #28 on: November 22, 2020, 10:13:49 AM »
do it the easy way. An astute driver will keep an eye on traffic closing in from behind. If the situations dictates, then a couple short taps on the brake will inform the rear traffic to pay attention. I don't think it is wise at all and is misleading if the brake lights are triggered by the jakes.
Don F
1976 MCI/TMC MC-8 #1286
Fully converted
Bought 2017

Offline richard5933

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Re: Brake lights stay on
« Reply #29 on: November 22, 2020, 10:50:20 AM »
I think this all depends on how strong the Jakes are. If they are like on a modern semi where they'll send you through the windshield, then perhaps the brake lights should be activated. However, if they're like mine where they just hold you at speed as you descend then having them on the entire time would mean that the driver behind you will never know when you use the service brakes with stab braking to drop your speed.
Richard
1974 GMC P8M4108a-125 Custom Coach "Land Cruiser" (Sold)
1964 GM PD4106-2412 (Former Bus)
1994 Airstream Excella 25-ft w/ 1999 Suburban 2500
Located in beautiful Wisconsin

 

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