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New LED front turn lights not working right...

SB
Shawn Bennear
Sun, Jun 21, 2020 2:12 PM

I recently installed a set of front LED parking/turn signal lights... I am having a wee bit of an issue, as follows...
during the day the turn signals work perfectly fine. turn on the parking lights, and that's all I have. no more turn signals. I do have the electronic
flasher installed, and they work fine during the day. turn the lights on, shows over.

Trying to figure out whats wrong with it. Do I need to hard wire instead of using the socket?

http://www.gmcmotorhomeworld.com

1977 Palm Beach, 403 V8 w headers.

I recently installed a set of front LED parking/turn signal lights... I am having a wee bit of an issue, as follows... during the day the turn signals work perfectly fine. turn on the parking lights, and that's all I have. no more turn signals. I do have the electronic flasher installed, and they work fine during the day. turn the lights on, shows over. Trying to figure out whats wrong with it. Do I need to hard wire instead of using the socket? -- http://www.gmcmotorhomeworld.com 1977 Palm Beach, 403 V8 w headers.
CB
Charles Boyd
Sun, Jun 21, 2020 2:57 PM

Sir, it sounds like possibly you have the 2 hot wires crossed.  Bright side is on with parks and dim side flashes and is not seen.

Shawn Bennear wrote on Sun, 21 June 2020 10:12

I recently installed a set of front LED parking/turn signal lights... I am having a wee bit of an issue, as follows...
during the day the turn signals work perfectly fine. turn on the parking lights, and that's all I have. no more turn signals. I do have the
electronic flasher installed, and they work fine during the day. turn the lights on, shows over.

Trying to figure out whats wrong with it. Do I need to hard wire instead of using the socket?

--
C. Boyd
76 Crestmont
East Tennessee

Sir, it sounds like possibly you have the 2 hot wires crossed. Bright side is on with parks and dim side flashes and is not seen. Shawn Bennear wrote on Sun, 21 June 2020 10:12 > I recently installed a set of front LED parking/turn signal lights... I am having a wee bit of an issue, as follows... > during the day the turn signals work perfectly fine. turn on the parking lights, and that's all I have. no more turn signals. I do have the > electronic flasher installed, and they work fine during the day. turn the lights on, shows over. > > Trying to figure out whats wrong with it. Do I need to hard wire instead of using the socket? -- C. Boyd 76 Crestmont East Tennessee
MC
Matt Colie
Sun, Jun 21, 2020 8:43 PM

Shawn Bennear wrote on Sun, 21 June 2020 10:12

I recently installed a set of front LED parking/turn signal lights... I am having a wee bit of an issue, as follows...
during the day the turn signals work perfectly fine. turn on the parking lights, and that's all I have. no more turn signals. I do have the
electronic flasher installed, and they work fine during the day. turn the lights on, shows over.

Trying to figure out whats wrong with it. Do I need to hard wire instead of using the socket?

Shawn,

Be patient, I am sure we can figure this out.

Did you install a single replacement for 1157 LED in an OE front marker / signal light housing?
You say it works with the marker lights off, but please give a better description of what happens when you turn on the marker lights.
Do the lights come on and stay on (on, but no flash)?
Or, do you just get nothing?

There is a very high (outrageously high) probability that there is a bad ground in the marker light assembly.  I have had to build in a new ground on
all of mine.

Matt

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

Shawn Bennear wrote on Sun, 21 June 2020 10:12 > I recently installed a set of front LED parking/turn signal lights... I am having a wee bit of an issue, as follows... > during the day the turn signals work perfectly fine. turn on the parking lights, and that's all I have. no more turn signals. I do have the > electronic flasher installed, and they work fine during the day. turn the lights on, shows over. > > Trying to figure out whats wrong with it. Do I need to hard wire instead of using the socket? Shawn, Be patient, I am sure we can figure this out. Did you install a single replacement for 1157 LED in an OE front marker / signal light housing? You say it works with the marker lights off, but please give a better description of what happens when you turn on the marker lights. Do the lights come on and stay on (on, but no flash)? Or, do you just get nothing? There is a very high (outrageously high) probability that there is a bad ground in the marker light assembly. I have had to build in a new ground on all of mine. Matt -- Matt & Mary Colie - '73 Glacier 23 - Members GMCMI, GMCGL, GMCES Electronically Controlled Quiet Engine Cooling Fan OE Rear Drum Brakes with Applied Control Arms SE Michigan - Twixt A2 and Detroit
SB
Shawn Bennear
Mon, Jun 22, 2020 1:28 AM

Matt Colie wrote on Sun, 21 June 2020 16:43

Shawn Bennear wrote on Sun, 21 June 2020 10:12

I recently installed a set of front LED parking/turn signal lights... I am having a wee bit of an issue, as follows...
during the day the turn signals work perfectly fine. turn on the parking lights, and that's all I have. no more turn signals. I do have the
electronic flasher installed, and they work fine during the day. turn the lights on, shows over.

Trying to figure out whats wrong with it. Do I need to hard wire instead of using the socket?

Shawn,

Be patient, I am sure we can figure this out.

Did you install a single replacement for 1157 LED in an OE front marker / signal light housing?
You say it works with the marker lights off, but please give a better description of what happens when you turn on the marker lights.
Do the lights come on and stay on (on, but no flash)?
Or, do you just get nothing?

There is a very high (outrageously high) probability that there is a bad ground in the marker light assembly.  I have had to build in a new ground
on all of mine.

Matt

Matt, No, I installed the whole complete one with about 30 led's in it on a circuit board...

--
http://www.gmcmotorhomeworld.com

1977 Palm Beach, 403 V8 w headers.

Matt Colie wrote on Sun, 21 June 2020 16:43 > Shawn Bennear wrote on Sun, 21 June 2020 10:12 > > I recently installed a set of front LED parking/turn signal lights... I am having a wee bit of an issue, as follows... > > during the day the turn signals work perfectly fine. turn on the parking lights, and that's all I have. no more turn signals. I do have the > > electronic flasher installed, and they work fine during the day. turn the lights on, shows over. > > > > Trying to figure out whats wrong with it. Do I need to hard wire instead of using the socket? > > Shawn, > > Be patient, I am sure we can figure this out. > > Did you install a single replacement for 1157 LED in an OE front marker / signal light housing? > You say it works with the marker lights off, but please give a better description of what happens when you turn on the marker lights. > Do the lights come on and stay on (on, but no flash)? > Or, do you just get nothing? > > > There is a very high (outrageously high) probability that there is a bad ground in the marker light assembly. I have had to build in a new ground > on all of mine. > > Matt Matt, No, I installed the whole complete one with about 30 led's in it on a circuit board... -- http://www.gmcmotorhomeworld.com 1977 Palm Beach, 403 V8 w headers.
BW
Bill Wevers
Mon, Jun 22, 2020 4:52 AM

The 1975 schematic shows two circuits with 1157 bulb. The park
light filament is wired to the same circuit as the side marker lights.
The park lights are low intensity filament (purple wire).
The turn signal is wired (blue wire) to the high intensity filament.

Maybe the two input wires to the new LED lights are swapped so
that you always have high intensity when the park lights are on.
And the turn signals are low intensity.

--
Bill Wevers  GMC49ers, GMC Western States
1975 Glenbrook - Manny Powerdrive, OneTon
455 F Block, G heads
San Jose

The 1975 schematic shows two circuits with 1157 bulb. The park light filament is wired to the same circuit as the side marker lights. The park lights are low intensity filament (purple wire). The turn signal is wired (blue wire) to the high intensity filament. Maybe the two input wires to the new LED lights are swapped so that you always have high intensity when the park lights are on. And the turn signals are low intensity. -- Bill Wevers GMC49ers, GMC Western States 1975 Glenbrook - Manny Powerdrive, OneTon 455 F Block, G heads San Jose
MC
Matt Colie
Mon, Jun 22, 2020 12:25 PM

Shawn Bennear wrote on Sun, 21 June 2020 21:28

Matt Colie wrote on Sun, 21 June 2020 16:43

Shawn Bennear wrote on Sun, 21 June 2020 10:12

I recently installed a set of front LED parking/turn signal lights... I am having a wee bit of an issue, as follows...
during the day the turn signals work perfectly fine. turn on the parking lights, and that's all I have. no more turn signals. I do have
the electronic flasher installed, and they work fine during the day. turn the lights on, shows over.

Trying to figure out whats wrong with it. Do I need to hard wire instead of using the socket?

Shawn,

Be patient, I am sure we can figure this out.

Did you install a single replacement for 1157 LED in an OE front marker / signal light housing?
You say it works with the marker lights off, but please give a better description of what happens when you turn on the marker lights.
Do the lights come on and stay on (on, but no flash)?
Or, do you just get nothing?

There is a very high (outrageously high) probability that there is a bad ground in the marker light assembly.  I have had to build in a new
ground on all of mine.

Matt

Matt, No, I installed the whole complete one with about 30 led's in it on a circuit board...

Shawn,
That is a nice looking part, but you still did not completely describe the issue:
Do the lights come on and stay on (on, but no flash)?
Or, do you just get nothing?
Matt

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

Shawn Bennear wrote on Sun, 21 June 2020 21:28 > Matt Colie wrote on Sun, 21 June 2020 16:43 > > Shawn Bennear wrote on Sun, 21 June 2020 10:12 > > > I recently installed a set of front LED parking/turn signal lights... I am having a wee bit of an issue, as follows... > > > during the day the turn signals work perfectly fine. turn on the parking lights, and that's all I have. no more turn signals. I do have > > > the electronic flasher installed, and they work fine during the day. turn the lights on, shows over. > > > > > > Trying to figure out whats wrong with it. Do I need to hard wire instead of using the socket? > > > > Shawn, > > > > Be patient, I am sure we can figure this out. > > > > Did you install a single replacement for 1157 LED in an OE front marker / signal light housing? > > You say it works with the marker lights off, but please give a better description of what happens when you turn on the marker lights. > > Do the lights come on and stay on (on, but no flash)? > > Or, do you just get nothing? > > > > > > There is a very high (outrageously high) probability that there is a bad ground in the marker light assembly. I have had to build in a new > > ground on all of mine. > > > > Matt > > Matt, No, I installed the whole complete one with about 30 led's in it on a circuit board... Shawn, That is a nice looking part, but you still did not completely describe the issue: Do the lights come on and stay on (on, but no flash)? Or, do you just get nothing? Matt -- Matt & Mary Colie - '73 Glacier 23 - Members GMCMI, GMCGL, GMCES Electronically Controlled Quiet Engine Cooling Fan OE Rear Drum Brakes with Applied Control Arms SE Michigan - Twixt A2 and Detroit
TL
Tom Lins
Mon, Jun 22, 2020 2:44 PM

Matt Colie wrote on Mon, 22 June 2020 08:25

Shawn Bennear wrote on Sun, 21 June 2020 21:28

Matt Colie wrote on Sun, 21 June 2020 16:43

Shawn Bennear wrote on Sun, 21 June 2020 10:12

I recently installed a set of front LED parking/turn signal lights... I am having a wee bit of an issue, as follows...
during the day the turn signals work perfectly fine. turn on the parking lights, and that's all I have. no more turn signals. I do
have the electronic flasher installed, and they work fine during the day. turn the lights on, shows over.

Trying to figure out whats wrong with it. Do I need to hard wire instead of using the socket?

Shawn,

Be patient, I am sure we can figure this out.

Did you install a single replacement for 1157 LED in an OE front marker / signal light housing?
You say it works with the marker lights off, but please give a better description of what happens when you turn on the marker lights.
Do the lights come on and stay on (on, but no flash)?
Or, do you just get nothing?

There is a very high (outrageously high) probability that there is a bad ground in the marker light assembly.  I have had to build in a
new ground on all of mine.

Matt

Matt, No, I installed the whole complete one with about 30 led's in it on a circuit board...

Shawn,
That is a nice looking part, but you still did not completely describe the issue:
Do the lights come on and stay on (on, but no flash)?
Or, do you just get nothing?
Matt

If I remember correctly there is an issue with using LEDs in the turn signal/front marker light circuit.
The side marker light gets it's ground from the filament of the front turn bulb and the LED will not allow the reverse path like a incandescent blub
will.
Look thru the archives I think there is a solution there.

--
Tom Lins
St Augustine, FL
77 GM Rear Twin, Dry Bath, 455,  Aluminum Radiator Quad-Bag Suspension  Solar Panel
Manuals on DVD
GMC Dealer Training Tapes
http://www.bdub.net/tomlins/

Matt Colie wrote on Mon, 22 June 2020 08:25 > Shawn Bennear wrote on Sun, 21 June 2020 21:28 > > Matt Colie wrote on Sun, 21 June 2020 16:43 > > > Shawn Bennear wrote on Sun, 21 June 2020 10:12 > > > > I recently installed a set of front LED parking/turn signal lights... I am having a wee bit of an issue, as follows... > > > > during the day the turn signals work perfectly fine. turn on the parking lights, and that's all I have. no more turn signals. I do > > > > have the electronic flasher installed, and they work fine during the day. turn the lights on, shows over. > > > > > > > > Trying to figure out whats wrong with it. Do I need to hard wire instead of using the socket? > > > > > > Shawn, > > > > > > Be patient, I am sure we can figure this out. > > > > > > Did you install a single replacement for 1157 LED in an OE front marker / signal light housing? > > > You say it works with the marker lights off, but please give a better description of what happens when you turn on the marker lights. > > > Do the lights come on and stay on (on, but no flash)? > > > Or, do you just get nothing? > > > > > > > > > There is a very high (outrageously high) probability that there is a bad ground in the marker light assembly. I have had to build in a > > > new ground on all of mine. > > > > > > Matt > > > > Matt, No, I installed the whole complete one with about 30 led's in it on a circuit board... > > Shawn, > That is a nice looking part, but you still did not completely describe the issue: > Do the lights come on and stay on (on, but no flash)? > Or, do you just get nothing? > Matt If I remember correctly there is an issue with using LEDs in the turn signal/front marker light circuit. The side marker light gets it's ground from the filament of the front turn bulb and the LED will not allow the reverse path like a incandescent blub will. Look thru the archives I think there is a solution there. -- Tom Lins St Augustine, FL 77 GM Rear Twin, Dry Bath, 455, Aluminum Radiator Quad-Bag Suspension Solar Panel Manuals on DVD GMC Dealer Training Tapes http://www.bdub.net/tomlins/
TL
Tom Lins
Mon, Jun 22, 2020 2:55 PM

https://groups.google.com/forum/#!searchin/gmcnet-archive/led$20turn%7Csort:date/gmcnet-archive/YUH0_WbiH58/alOaqYM5AgAJ

--
Tom Lins
St Augustine, FL
77 GM Rear Twin, Dry Bath, 455,  Aluminum Radiator Quad-Bag Suspension  Solar Panel
Manuals on DVD
GMC Dealer Training Tapes
http://www.bdub.net/tomlins/

https://groups.google.com/forum/#!searchin/gmcnet-archive/led$20turn%7Csort:date/gmcnet-archive/YUH0_WbiH58/alOaqYM5AgAJ -- Tom Lins St Augustine, FL 77 GM Rear Twin, Dry Bath, 455, Aluminum Radiator Quad-Bag Suspension Solar Panel Manuals on DVD GMC Dealer Training Tapes http://www.bdub.net/tomlins/
JW
John Wright
Mon, Jun 22, 2020 6:08 PM

Tom,
Your are correct on the front side marker/turn signal. It does not work with LED’s in the side marker position because of way the circuit is designed.  I have standard bulbs in this circuit.  I run all LED tail light assemblies in the rear with out issue and do run a mechanical flasher unit in both position on the steering column.

J.R. Wright
GMC Great Laker MHC
GMCGL Tech Editor
GMC Eastern States Charter Member
GMCMI
78 GMC Buskirk 29.5’ Stretch
75 GMC Avion (Under Reconstruction)
Michigan

On Jun 22, 2020, at 10:55 AM, Tom Lins via Gmclist gmclist@list.gmcnet.org wrote:

https://groups.google.com/forum/#!searchin/gmcnet-archive/led$20turn%7Csort:date/gmcnet-archive/YUH0_WbiH58/alOaqYM5AgAJ

--
Tom Lins
St Augustine, FL
77 GM Rear Twin, Dry Bath, 455,  Aluminum Radiator Quad-Bag Suspension  Solar Panel
Manuals on DVD
GMC Dealer Training Tapes
http://www.bdub.net/tomlins/


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Tom, Your are correct on the front side marker/turn signal. It does not work with LED’s in the side marker position because of way the circuit is designed. I have standard bulbs in this circuit. I run all LED tail light assemblies in the rear with out issue and do run a mechanical flasher unit in both position on the steering column. J.R. Wright GMC Great Laker MHC GMCGL Tech Editor GMC Eastern States Charter Member GMCMI 78 GMC Buskirk 29.5’ Stretch 75 GMC Avion (Under Reconstruction) Michigan > On Jun 22, 2020, at 10:55 AM, Tom Lins via Gmclist <gmclist@list.gmcnet.org> wrote: > > https://groups.google.com/forum/#!searchin/gmcnet-archive/led$20turn%7Csort:date/gmcnet-archive/YUH0_WbiH58/alOaqYM5AgAJ > > > -- > Tom Lins > St Augustine, FL > 77 GM Rear Twin, Dry Bath, 455, Aluminum Radiator Quad-Bag Suspension Solar Panel > Manuals on DVD > GMC Dealer Training Tapes > http://www.bdub.net/tomlins/ > > _______________________________________________ > GMCnet mailing list > Unsubscribe or Change List Options: > http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
ES
Eric Schmidt
Sat, Apr 2, 2022 5:06 PM

When installing LED bulbs for the turn/brake light signal system, you must use electronic flashers, and the front side marker lights need to be
"non-polarity" sensitive. The front parking light switches the ground on the side marker light during the flashing process, so if it is polarity
sensitive, it will not work. If you look at specs of the bulbs they will generally specify this, but if they don't, assume that they are polarity
sensitive. I never would have guessed these bulbs even existed, knowing LEDs are typically polarity sensitive! Mine all work correctly now after
learning and doing this.

When installing LED bulbs for the turn/brake light signal system, you must use electronic flashers, and the front side marker lights need to be "non-polarity" sensitive. The front parking light switches the ground on the side marker light during the flashing process, so if it is polarity sensitive, it will not work. If you look at specs of the bulbs they will generally specify this, but if they don't, assume that they are polarity sensitive. I never would have guessed these bulbs even existed, knowing LEDs are typically polarity sensitive! Mine all work correctly now after learning and doing this.