Now what... still no rear turns or brake lights

C

charles boyd

New member
Jul 8, 2007
3,462
2
0
Sir, as you know the turn and brake lights are the same bright filament in the bulb and the park lights are a separate dim circuit on a different
filament on the bulb. Look at the bulbs as the mounting bayonet style pins are offset and only go 1 way right. I have done them wrong with a little
force. Is the brake light switch working? It is on the top of brake pedal bracket. The turn signals are powered all the time and the switch selects
right or left. A tidbit of info Is the park lights will work without a good ground but the brake and turn signals won’t. They will try to ground
thru the dim parking light and will cut it off and on like it is blinking but the bright side should be coming on when the dim one goes out with a
good ground. Sometimes the later GMC taillights are installed and they require a ground for each bulb.

--
C. Boyd
76 Crestmont
East Tennessee
 
Its all new guts, including brake switches. Also running Led bulbs,, which worked before
the rig sat. Is there a common ground in the body harness? My rig is number 1885 off the assemblyline. So its a 73. I doubt both LED bulbs would go

> Sir, as you know the turn and brake lights are the same bright filament in the bulb and the park lights are a separate dim circuit on a different
> filament on the bulb. Look at the bulbs as the mounting bayonet style pins are offset and only go 1 way right. I have done them wrong with a
> little force. Is the brake light switch working? It is on the top of brake pedal bracket. The turn signals are powered all the time and the switch
> selects right or left. A tidbit of info Is the park lights will work without a good ground but the brake and turn signals won’t. They will try
> to ground thru the dim parking light and will cut it off and on like it is blinking but the bright side should be coming on when the dim one goes
> out with a good ground. Sometimes the later GMC taillights are installed and they require a ground for each bulb.

--
73 Canyon Lands, (a.k.a. The Yellow Submarine) West Los Angeles CA
 
LED lamps are polarity sensitive. Maybe that's your problem, Shan.

Haven't seen you on here in quite a while. Still using the XD Star wheels?
I bought a set in chrome for my coach.

D C "Mac" Macdonald
Amateur Radio K2GKK
Since 30 November '53
USAF and FAA, Retired
Member GMCMI & Classics
Oklahoma City, OK
"The Money Pit"
TZE166V101966
'76 ex-Palm Beach
k2gkk + hotmail dot com

________________________________
From: Shan Rose
Sent: Tuesday, March 30, 2021 21:00
To: gmclist
Subject: [GMCnet] Re: Now what... still no rear turns or brake lights

Its all new guts, including brake switches. Also running Led bulbs,, which worked before
the rig sat. Is there a common ground in the body harness? My rig is number 1885 off the assemblyline. So its a 73. I doubt both LED bulbs would go

> Sir, as you know the turn and brake lights are the same bright filament in the bulb and the park lights are a separate dim circuit on a different
> filament on the bulb. Look at the bulbs as the mounting bayonet style pins are offset and only go 1 way right. I have done them wrong with a
> little force. Is the brake light switch working? It is on the top of brake pedal bracket. The turn signals are powered all the time and the switch
> selects right or left. A tidbit of info Is the park lights will work without a good ground but the brake and turn signals won’t. They will try
> to ground thru the dim parking light and will cut it off and on like it is blinking but the bright side should be coming on when the dim one goes
> out with a good ground. Sometimes the later GMC taillights are installed and they require a ground for each bulb.

73 Canyon Lands, (a.k.a. The Yellow Submarine) West Los Angeles CA
 
Aside from some bad curb rash thanks to lil brother, gf, and a tire shop incapable of mounting truck tires after 10 years the XDs held up well. Thing
with the bulbs was they worked fine before I came up here to nor can and coach sat for 9 months. Thanks to pandemic cash im finally able to address a

2021 19:14
> LED lamps are polarity sensitive. Maybe that's your problem, Shan.
>
> Haven't seen you on here in quite a while. Still using the XD Star wheels?
> I bought a set in chrome for my coach.
>
> D C "Mac" Macdonald
> Amateur Radio K2GKK
> Since 30 November '53
> USAF and FAA, Retired
> Member GMCMI & Classics
> Oklahoma City, OK
> "The Money Pit"
> TZE166V101966
> '76 ex-Palm Beach
> k2gkk + hotmail dot com
>
> ________________________________
> From: Shan Rose
> Sent: Tuesday, March 30, 2021 21:00
> To: gmclist
> Subject: [GMCnet] Re: Now what... still no rear turns or brake lights
>
> Its all new guts, including brake switches. Also running Led bulbs,, which worked before
> the rig sat. Is there a common ground in the body harness? My rig is number 1885 off the assemblyline. So its a 73. I doubt both LED bulbs would
> go

> > Sir, as you know the turn and brake lights are the same bright filament in the bulb and the park lights are a separate dim circuit on a
> > different
> > filament on the bulb. Look at the bulbs as the mounting bayonet style pins are offset and only go 1 way right. I have done them wrong with
> > a
> > little force. Is the brake light switch working? It is on the top of brake pedal bracket. The turn signals are powered all the time and the
> > switch
> > selects right or left. A tidbit of info Is the park lights will work without a good ground but the brake and turn signals won’t. They
> > will try
> > to ground thru the dim parking light and will cut it off and on like it is blinking but the bright side should be coming on when the dim one
> > goes
> > out with a good ground. Sometimes the later GMC taillights are installed and they require a ground for each bulb.
>
> 73 Canyon Lands, (a.k.a. The Yellow Submarine) West Los Angeles CA
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:

--
73 Canyon Lands, (a.k.a. The Yellow Submarine) West Los Angeles CA
 
Mike you were looking for a valve for your stove. I had written an email some time ago saying that I had located a used one at an RV shop.
I didn’t see a reply from you. Do you still need one?
Emery Stora
emerystora

>
> Aside from some bad curb rash thanks to lil brother, gf, and a tire shop incapable of mounting truck tires after 10 years the XDs held up well. Thing
> with the bulbs was they worked fine before I came up here to nor can and coach sat for 9 months. Thanks to pandemic cash im finally able to address a

> 2021 19:14
>> LED lamps are polarity sensitive. Maybe that's your problem, Shan.
>>
>> Haven't seen you on here in quite a while. Still using the XD Star wheels?
>> I bought a set in chrome for my coach.
>>
>> D C "Mac" Macdonald
>> Amateur Radio K2GKK
>> Since 30 November '53
>> USAF and FAA, Retired
>> Member GMCMI & Classics
>> Oklahoma City, OK
>> "The Money Pit"
>> TZE166V101966
>> '76 ex-Palm Beach
>> k2gkk + hotmail dot com
>>
>> ________________________________
>> From: Shan Rose
>> Sent: Tuesday, March 30, 2021 21:00
>> To: gmclist
>> Subject: [GMCnet] Re: Now what... still no rear turns or brake lights
>>
>> Its all new guts, including brake switches. Also running Led bulbs,, which worked before
>> the rig sat. Is there a common ground in the body harness? My rig is number 1885 off the assemblyline. So its a 73. I doubt both LED bulbs would
>> go

>>> Sir, as you know the turn and brake lights are the same bright filament in the bulb and the park lights are a separate dim circuit on a
>>> different
>>> filament on the bulb. Look at the bulbs as the mounting bayonet style pins are offset and only go 1 way right. I have done them wrong with
>>> a
>>> little force. Is the brake light switch working? It is on the top of brake pedal bracket. The turn signals are powered all the time and the
>>> switch
>>> selects right or left. A tidbit of info Is the park lights will work without a good ground but the brake and turn signals won’t. They
>>> will try
>>> to ground thru the dim parking light and will cut it off and on like it is blinking but the bright side should be coming on when the dim one
>>> goes
>>> out with a good ground. Sometimes the later GMC taillights are installed and they require a ground for each bulb.
>>
>> 73 Canyon Lands, (a.k.a. The Yellow Submarine) West Los Angeles CA
>>
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>
>
> --
> 73 Canyon Lands, (a.k.a. The Yellow Submarine) West Los Angeles CA
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
 
Well it must be grounding out somewhere. I'm hoping just a connection in the body harness as everything else works, where's the junctio from the dash
to body harness?
--
73 Canyon Lands, (a.k.a. The Yellow Submarine) West Los Angeles CA
 
Sir, you said you changed the turn signal switch? The last few I got had the wrong plug on the switch where it plugs to the body harness on the
outside of the steering column. Maybe check to see if it is connected straight and tight. If it is check to see if your brake light switch is
getting 12 v , both sides when pedal is pressed. If you drop the bottom cover it is easy to see.

> Well it must be grounding out somewhere. I'm hoping just a connection in the body harness as everything else works, where's the junctio from the
> dash to body harness?

--
C. Boyd
76 Crestmont
East Tennessee
 
Fix the ground side of the circuit. You have the symptom of an open ground at the tail Light(s). If you can not diagnose the problem with a meter,
Get 30 to 35 feet of any size wire from 18 to 12 gauge. Connect one end directly to the ENGINE battery negative terminal. Then temporarily connect
the other end to each failing light, one at a time. If the light works correctly, then you have bypassed the open ground and proven that you have a
ground problem.
--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
 
> Sir, you said you changed the turn signal switch? The last few I got had the wrong plug on the switch where it plugs to the body harness on the
> outside of the steering column. Maybe check to see if it is connected straight and tight. If it is check to see if your brake light switch is
> getting 12 v , both sides when pedal is pressed. If you drop the bottom cover it is easy to see.
>
>
>
>
>
>
>

> > Well it must be grounding out somewhere. I'm hoping just a connection in the body harness as everything else works, where's the junctio from
> > the dash to body harness?

--
73 Canyon Lands, (a.k.a. The Yellow Submarine) West Los Angeles CA
 
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