'brake' light on dash. what does it mean?

Matt Colie

Well-known member
Aug 15, 2008
11,101
807
113
South East Michigan near DTW
'brake' light on dash. what does it mean?

Charles,

It is installed to have two indications:

1 - Indicate that there is an imbalance between the front and rear brake circuits. (You lost a brake system.)
2 - Indicate that the parking brake lever is in the "set" position. This has a high failure rate.

I hope this help.

Matt

--
Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit
 
Matt..

Where is the actual switch that reports to the "PARK BRAKE" Tell-Tale display?

I see two brake switches on the electrical diagram... One is the "Differential Brake Switch", which I assume is the combination valve. That lights a
'Brake' light on the instrument cluster. The other is an unlabeled switch that lights a section of the Tell Tale display.

--
Bill Van Vlack
'76 Royale; Guemes Island, Washington; Twin bed, full (DS) side bath, Brazilian Redwood counter and settee tops,455, 6KW generator; new owner a/o mid
November 2015.
 
> Matt..
>
> Where is the actual switch that reports to the "PARK BRAKE" Tell-Tale display?
>
> I see two brake switches on the electrical diagram... One is the "Differential Brake Switch", which I assume is the combination valve. That
> lights a 'Brake' light on the instrument cluster. The other is an unlabeled switch that lights a section of the Tell Tale display.

Bill,

That switch is just a set of contacts on the outboard side of the parking brake lever. I have seen mine, but it is too close to the side of the cab
for me to do anything like make it actually work. If someday I have to have that lever off, then I might go after that as it would be nice to have.

Matt
--
Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit
 
Well, I know when I accidentally left my parking brake on while driving the coach from Texas, no lights lit. It was only after the brakes got hot and
I glided through a red light with NO brakes that the

"Brake" light came on.

So, on mine at least, I think there is a different (currently non-working) light to indicate stupidity, er, I mean leaving the parking brake on.

Coach is currently in my driveway on blocks undergoing brake renewal.
--
Greg Crawford
Knoxville, TN

1977 Royale
403
Rear Bath
American Eagle Wheels
Alex Sirum Quad bags
 
There are actually two brake lights on the dash. One in the speedometer cluster is actuated by the switch on the side of the parking bracket by the floor. The other is in the warning light cluster. This is actuated by the Brake combination Switch which is located in the brake lines on the frame inside the driver’s side front wheel. There is a wire on the top that comes on if the spindle inside the switch moves either forward or back indicating a failure or low fluid either in the front or rear brakes.

Emery Stora
77 Kingsley
Frederick CO

>
> Well, I know when I accidentally left my parking brake on while driving the coach from Texas, no lights lit. It was only after the brakes got hot and
> I glided through a red light with NO brakes that the
>
> "Brake" light came on.
>
> So, on mine at least, I think there is a different (currently non-working) light to indicate stupidity, er, I mean leaving the parking brake on.
>
>
> Coach is currently in my driveway on blocks undergoing brake renewal.
> --
> Greg Crawford
> Knoxville, TN
>
> 1977 Royale
> 403
> Rear Bath
> American Eagle Wheels
> Alex Sirum Quad bags
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
 
There is no warning light that tells the driver that the e-brake is still
on, that the factory installed. There should be, that is for certain. If
you really want to glaze your rear drums, just drive a few miles with the
e-brake on. If you are rebuilding your brakes, always deglaze your drums.
Jim Hupy
Salem ,Oregon

On Fri, Aug 21, 2020, 4:33 PM Emery Stora via Gmclist <

> There are actually two brake lights on the dash. One in the speedometer
> cluster is actuated by the switch on the side of the parking bracket by the
> floor. The other is in the warning light cluster. This is actuated by the
> Brake combination Switch which is located in the brake lines on the frame
> inside the driver’s side front wheel. There is a wire on the top that comes
> on if the spindle inside the switch moves either forward or back indicating
> a failure or low fluid either in the front or rear brakes.
>
> Emery Stora
> 77 Kingsley
> Frederick CO
>
> > On Aug 21, 2020, at 5:21 PM, Greg Crawford via Gmclist <

> >
> > Well, I know when I accidentally left my parking brake on while driving
> the coach from Texas, no lights lit. It was only after the brakes got hot
> and
> > I glided through a red light with NO brakes that the
> >
> > "Brake" light came on.
> >
> > So, on mine at least, I think there is a different (currently
> non-working) light to indicate stupidity, er, I mean leaving the parking
> brake on.
> >
> >
> > Coach is currently in my driveway on blocks undergoing brake renewal.
> > --
> > Greg Crawford
> > Knoxville, TN
> >
> > 1977 Royale
> > 403
> > Rear Bath
> > American Eagle Wheels
> > Alex Sirum Quad bags
> >
> > _______________________________________________
> > GMCnet mailing list
> > Unsubscribe or Change List Options:
> > http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
 
Jim — you are wrong on this one. I seldom have found you in error but you are this time.

I have a 1977 Kingsley. In the Owner’s Operating Manual for 1977 on page 24 t says:

To help remind you, the “Park Brake” light is designed to come on if the parking brake control is not fully released and the ignition key is on.

I believe you have a 1978 Royale. On page 18 of the 1978 Transmode manual it says:

To help remind you, the “Park Brake” light is designed to come on if the parking brake control is not fully released and the ignition key is on.

I even checked the 1973 Owner’s Operating Manual and it also says:

To help remind you, the “Park Brake” light is designed to come on if the parking brake control is not fully released and the ignition key is on.

So it appears that GMC installed this on all models.

Emery Stora
77 Kingsley
Frederick, CO

>
> There is no warning light that tells the driver that the e-brake is still
> on, that the factory installed. There should be, that is for certain. If
> you really want to glaze your rear drums, just drive a few miles with the
> e-brake on. If you are rebuilding your brakes, always deglaze your drums.
> Jim Hupy
> Salem ,Oregon
>
> On Fri, Aug 21, 2020, 4:33 PM Emery Stora via Gmclist <

>
>> There are actually two brake lights on the dash. One in the speedometer
>> cluster is actuated by the switch on the side of the parking bracket by the
>> floor. The other is in the warning light cluster. This is actuated by the
>> Brake combination Switch which is located in the brake lines on the frame
>> inside the driver’s side front wheel. There is a wire on the top that comes
>> on if the spindle inside the switch moves either forward or back indicating
>> a failure or low fluid either in the front or rear brakes.
>>
>> Emery Stora
>> 77 Kingsley
>> Frederick CO
>>
>>> On Aug 21, 2020, at 5:21 PM, Greg Crawford via Gmclist <

>>>
>>> Well, I know when I accidentally left my parking brake on while driving
>> the coach from Texas, no lights lit. It was only after the brakes got hot
>> and
>>> I glided through a red light with NO brakes that the
>>>
>>> "Brake" light came on.
>>>
>>> So, on mine at least, I think there is a different (currently
>> non-working) light to indicate stupidity, er, I mean leaving the parking
>> brake on.
>>>
>>>
>>> Coach is currently in my driveway on blocks undergoing brake renewal.
>>> --
>>> Greg Crawford
>>> Knoxville, TN
>>>
>>> 1977 Royale
>>> 403
>>> Rear Bath
>>> American Eagle Wheels
>>> Alex Sirum Quad bags
>>>
>>> _______________________________________________
>>> GMCnet mailing list
>>> Unsubscribe or Change List Options:
>>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
 
James - it just occurred to me that perhaps your dash bulb is burned out for the parking brake warning light.

Emery Stora

>
> There is no warning light that tells the driver that the e-brake is still
> on, that the factory installed. There should be, that is for certain. If
> you really want to glaze your rear drums, just drive a few miles with the
> e-brake on. If you are rebuilding your brakes, always deglaze your drums.
> Jim Hupy
> Salem ,Oregon
>
> On Fri, Aug 21, 2020, 4:33 PM Emery Stora via Gmclist <

>
>> There are actually two brake lights on the dash. One in the speedometer
>> cluster is actuated by the switch on the side of the parking bracket by the
>> floor. The other is in the warning light cluster. This is actuated by the
>> Brake combination Switch which is located in the brake lines on the frame
>> inside the driver’s side front wheel. There is a wire on the top that comes
>> on if the spindle inside the switch moves either forward or back indicating
>> a failure or low fluid either in the front or rear brakes.
>>
>> Emery Stora
>> 77 Kingsley
>> Frederick CO
>>
>>> On Aug 21, 2020, at 5:21 PM, Greg Crawford via Gmclist <

>>>
>>> Well, I know when I accidentally left my parking brake on while driving
>> the coach from Texas, no lights lit. It was only after the brakes got hot
>> and
>>> I glided through a red light with NO brakes that the
>>>
>>> "Brake" light came on.
>>>
>>> So, on mine at least, I think there is a different (currently
>> non-working) light to indicate stupidity, er, I mean leaving the parking
>> brake on.
>>>
>>>
>>> Coach is currently in my driveway on blocks undergoing brake renewal.
>>> --
>>> Greg Crawford
>>> Knoxville, TN
>>>
>>> 1977 Royale
>>> 403
>>> Rear Bath
>>> American Eagle Wheels
>>> Alex Sirum Quad bags
>>>
>>> _______________________________________________
>>> GMCnet mailing list
>>> Unsubscribe or Change List Options:
>>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
 
Emery's right on this one. I know because I broke my switch while removing and reinstalling the side panel next to the driver's seat. Hope I can
find a replacement or fab a substitute.

Rick Staples

--
Rick Staples, '75 Eleganza, Johnstown, CO

"Advice is a dangerous gift, even from the Wise to the Wise, and all paths may run ill." -Tolkien
 
Well son of a gun. I stand corrected. I provided information that misled
people out there, I am truly sorry. I have never seen a functioning warning
light for leaving the parking brake applied, so I just ASS U MED that there
wasn't one. I was wrong.
Jim Hupy
Salem, Oregon

On Fri, Aug 21, 2020, 6:37 PM Richard H Staples via Gmclist <

> Emery's right on this one. I know because I broke my switch while
> removing and reinstalling the side panel next to the driver's seat. Hope I
> can
> find a replacement or fab a substitute.
>
> Rick Staples
>
>
> --
> Rick Staples, '75 Eleganza, Johnstown, CO
>
> "Advice is a dangerous gift, even from the Wise to the Wise, and all paths
> may run ill." -Tolkien
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
 
Darn you guys and your nit-picking!!! You should know I'd have to look at
the wiring diagram!

Emery, I hate to tell you this, but you got it bass ackards, at least on
the '75-'76 diagram: The lamp in the speedometer's connected to the
combination valve's differential pressure switch. The lamp in the
tell-tale cluster connects to the parking brake handle switch. I know,
that's bass ackards to how it OUGHT to be -- but it's the way it is.

Maybe some other years are different, but it's too late for me to go
checking tonight. :-)

Ken "Busy Body" H.

On Fri, Aug 21, 2020 at 9:45 PM James Hupy via Gmclist <

> Well son of a gun. I stand corrected. I provided information that misled
> people out there, I am truly sorry. I have never seen a functioning warning
> light for leaving the parking brake applied, so I just ASS U MED that there
> wasn't one. I was wrong.
> Jim Hupy
> Salem, Oregon
>
> On Fri, Aug 21, 2020, 6:37 PM Richard H Staples via Gmclist <

>
> > Emery's right on this one. I know because I broke my switch while
> > removing and reinstalling the side panel next to the driver's seat.
> Hope I
> > can
> > find a replacement or fab a substitute.
> >
> > Rick Staples
> >
> >
> > --
> > Rick Staples, '75 Eleganza, Johnstown, CO
> >
> > "Advice is a dangerous gift, even from the Wise to the Wise, and all
> paths
> > may run ill." -Tolkien
> >
> > _______________________________________________
> > GMCnet mailing list
> > Unsubscribe or Change List Options:
> > http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
> >
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
 
Ken
Don’t be so dammed right all the time. Every time you post about 50 people grab their books to see if you are correct!

Emery Stora

>
> Darn you guys and your nit-picking!!! You should know I'd have to look at
> the wiring diagram!
>
> Emery, I hate to tell you this, but you got it bass ackards, at least on
> the '75-'76 diagram: The lamp in the speedometer's connected to the
> combination valve's differential pressure switch. The lamp in the
> tell-tale cluster connects to the parking brake handle switch. I know,
> that's bass ackards to how it OUGHT to be -- but it's the way it is.
>
> Maybe some other years are different, but it's too late for me to go
> checking tonight. :-)
>
> Ken "Busy Body" H.
>
>
>> On Fri, Aug 21, 2020 at 9:45 PM James Hupy via Gmclist <

>>
>> Well son of a gun. I stand corrected. I provided information that misled
>> people out there, I am truly sorry. I have never seen a functioning warning
>> light for leaving the parking brake applied, so I just ASS U MED that there
>> wasn't one. I was wrong.
>> Jim Hupy
>> Salem, Oregon
>>
>> On Fri, Aug 21, 2020, 6:37 PM Richard H Staples via Gmclist <

>>
>>> Emery's right on this one. I know because I broke my switch while
>>> removing and reinstalling the side panel next to the driver's seat.
>> Hope I
>>> can
>>> find a replacement or fab a substitute.
>>>
>>> Rick Staples
>>>
>>>
>>> --
>>> Rick Staples, '75 Eleganza, Johnstown, CO
>>>
>>> "Advice is a dangerous gift, even from the Wise to the Wise, and all
>> paths
>>> may run ill." -Tolkien
>>>
>>> _______________________________________________
>>> GMCnet mailing list
>>> Unsubscribe or Change List Options:
>>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>>
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
 
Touche' :-)

Ken H.

On Sat, Aug 22, 2020 at 12:26 PM Emery Stora via Gmclist <

> Ken
> Don’t be so dammed right all the time. Every time you post about 50 people
> grab their books to see if you are correct!
>
> Emery Stora
>
> > On Aug 21, 2020, at 8:56 PM, Ken Henderson via Gmclist <

> >
> > Darn you guys and your nit-picking!!! You should know I'd have to look
> at
> > the wiring diagram!
> >
> > Emery, I hate to tell you this, but you got it bass ackards, at least on
> > the '75-'76 diagram: The lamp in the speedometer's connected to the
> > combination valve's differential pressure switch. The lamp in the
> > tell-tale cluster connects to the parking brake handle switch. I know,
> > that's bass ackards to how it OUGHT to be -- but it's the way it is.
> >
> > Maybe some other years are different, but it's too late for me to go
> > checking tonight. :-)
> >
> > Ken "Busy Body" H.
> >
> >
> >> On Fri, Aug 21, 2020 at 9:45 PM James Hupy via Gmclist <

> >>
> >> Well son of a gun. I stand corrected. I provided information that
> misled
> >> people out there, I am truly sorry. I have never seen a functioning
> warning
> >> light for leaving the parking brake applied, so I just ASS U MED that
> there
> >> wasn't one. I was wrong.
> >> Jim Hupy
> >> Salem, Oregon
> >>
> >> On Fri, Aug 21, 2020, 6:37 PM Richard H Staples via Gmclist <

> >>
> >>> Emery's right on this one. I know because I broke my switch while
> >>> removing and reinstalling the side panel next to the driver's seat.
> >> Hope I
> >>> can
> >>> find a replacement or fab a substitute.
> >>>
> >>> Rick Staples
> >>>
> >>>
> >>> --
> >>> Rick Staples, '75 Eleganza, Johnstown, CO
> >>>
> >>> "Advice is a dangerous gift, even from the Wise to the Wise, and all
> >> paths
> >>> may run ill." -Tolkien
> >>>
> >>> _______________________________________________
> >>> GMCnet mailing list
> >>> Unsubscribe or Change List Options:
> >>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
> >>>
> >> _______________________________________________
> >> GMCnet mailing list
> >> Unsubscribe or Change List Options:
> >> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
> >>
> > _______________________________________________
> > GMCnet mailing list
> > Unsubscribe or Change List Options:
> > http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
> _______________________________________________
> GMCnet mailing list
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>