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I switched over to led lights in the dash and center gauge with both led bulbs as well as rgb led strips. The led bulbs are turned on via the headlight switch and the rgb led strips are powered on when you turn the key to on.
Problem:
With the ignition key off/on and seat belts unbuckled/buckled seats occupied/unoccupied the seat belt light is always dim and won't turn off. In other words, my problem is the seat belt light will only turn off if I disconnect the battery and it's always dim, not bright.
I'm not sure if it's related to the led bulb conversion or it's a seat belt electrical issue, therefore I'm not sure if I need to remove the center gauge area and check the wiring or remove the seat and check the harness underneath the seat. If memory serves me right the seat belt light should only turn on with the ignition in the on position, seatbelt unbuckled and someone sitting in either the drivers or passenger seat?
Any suggestions before I remove the dash to investigate?
my best guess the problem is the seat belt switch,
the wire might be pinched creating a short, or it has some minor corrosion within the switch assemble,
and is slightly conducting all the time. fix the switch first.
then determine where power feed comes from 12v with switch on, or always 12volts.
also make sure the console bezel is grounded properly.
if you do not have proper ground, it can back feed thru leds seeking ground.
creating a dimly lit led.
I believe the switch is located in the seat belt buckle? Does the seat belt light activate on both the drivers and passenger side on the 1975? It's odd that this problem would occur at the same time I'm doing the led bulb mod which is why I wonder if it's the switch but then anything's possible.
I checked and the console is grounded as I needed to ensure in order to get the lights to work.
DUB
The led bulbs are wired into the headlight switch and the rgb led strips are wired into the radio power. I know it's not the strips as the strips are distributed throughout the center bezel and not in the 'seat belt light" area.
Below is a bench test of the rgb led strips in red (cell phone pic)
It's a 75 coupe.
Last edited by Maymyvetteliveforevr; 05-31-2017 at 08:58 PM.
I've found that with the ignition off, there is low voltage (unable to determine how much as I didn't have a multi meter) enough to light up the led, but not the stock incandescent bulb. When I connect the seat belts with ignition off, no one sitting in the seats, there is even less voltage (noted by the led dimming more).
It seems that the bulb socket works on ground?
I unplugged the seat belt buckle located in the center console (where the e-brake is located) and there was no change.
I placed another ground to the center gauge bezel and it made no difference.
I'm unable to turn the seat belt led bulb off (dim at all times).
OK...I will look tomorrow at work and see what I can find in the wiring diagram. I do not have one here at home.
What wire are your LEDs wired into at headlight switch???
When you say 'radio power' I am assuming the yellow wire that would power your stereo. AND are you ONLY using that yellow wire that is your radio wire power for the LEDs????...or are you ALSO using it for the radio?????....AND...is your stereo factory or aftermarket?????
What wire are your LEDs wired into at headlight switch???
DUB
The led bulbs are wired into the light switch and I thought there was only one power wire, either way, the rest of the led bulbs work fine except for the seat belt light.
Originally Posted by DUB
When you say 'radio power' I am assuming the yellow wire that would power your stereo. AND are you ONLY using that yellow wire that is your radio wire power for the LEDs????...or are you ALSO using it for the radio?????....AND...is your stereo factory or aftermarket?????
DUB
I used the radio wire for the led strips, my problem is with the led bulbs, not the strips. in other words, the led bulbs are wired into the headlight switch and can be dimmed. The led rgb stips are wired into the radio power and are turned off via a remote.
For sake of trouble shooting I should have not even mention the led rgb led strips as they're turned off and are not part of the problem. When changing over to the led's I installed two led set ups, the led bulbs would be used 90% of the time and the led rgb strips would be used only for effect and were on a separate circuit.
Last edited by Maymyvetteliveforevr; 06-06-2017 at 08:43 PM.
I've found that with the ignition off, there is low voltage (unable to determine how much as I didn't have a multi meter) enough to light up the led, but not the stock incandescent bulb. When I connect the seat belts with ignition off, no one sitting in the seats, there is even less voltage (noted by the led dimming more).
It seems that the bulb socket works on ground?
I unplugged the seat belt buckle located in the center console (where the e-brake is located) and there was no change.
I placed another ground to the center gauge bezel and it made no difference.
I'm unable to turn the seat belt led bulb off (dim at all times).
An LED takes very little current to start lighting up. You are probably only seeing a couple of volts.
Does it light up properly when it should?
Do you know what colours are used for this lamp? 1975 had two different systems for this. Earlier models had an interlock system (which was mostly bypassed due to problems with it) while later models had a more simple warning system. Knowing which yours is would make it easier.
No, with the led light installed it stays dim all the time even with the ignition off. I installed a red led bulb and I took possession of the car on Jan 3rd 1975 so it was an early model.
I was meaning when the lamp should be on does it light up properly?
If it was an early model that would mean when you got it then you would have had to have your seatbelt buckled up to start the car. (Unless the interlock system was bypassed before you took possession). With the interlocked system the seatbelt warning light is switched by a control unit. I suspect (I've never seen the inside of one) that it is a transistor switch for this. If that is true then to get your light to turn off fully then you'll need to install a relay, or swap back to a normal bulb. That's one of the flaws with solid state switching, they still allow a small current to flow, just enough that LEDs just start to light up.
I was meaning when the lamp should be on does it light up properly?
No, there is no change, therefore it does not. The only change is when I buckle up the seatbelt with no one sitting in the seat the led bulb gets a bit dimmer than it's present dimness. I'll assume the voltage is even lower.
Originally Posted by Antz81
If it was an early model that would mean when you got it then you would have had to have your seatbelt buckled up to start the car. (Unless the interlock system was bypassed before you took possession).
I purchased the car new at the GM dealership and no they did not bypass the seatbelt. I've actually never heard of having to buckle up the seatbelt in order to start a 75 model year.
Originally Posted by 69Vett
you do know some Leds can be installed backwards right ?
flip the LED if it is a bayonet type socket.
Yes, I'm aware of installing led's the correct way and I've turned the led around as well as installed two other identical type led's as I bought extras and there is no difference.
With the normal bulb it won't turn on at all.
Last edited by Maymyvetteliveforevr; 06-07-2017 at 12:33 PM.
No, with the led light installed it stays dim all the time even with the ignition off.
I am assuming that "IT" is the seat belt light??????...or is it that the LED's are staying lit????
This type of response is what confuses me due to when dealing with a problem...being extremely clear in what you are communicating... takes any doubt of what you are writing...which helps.
SO if the red led light is NOT installed..does the light stop being dim...which I am assuming is the seat belt light???
The led bulbs are wired into the light switch and I thought there was only one power wire, either way, the rest of the led bulbs work fine except for the seat belt light. Still.... It would be nice to know what color wire you attached your LED's to????
I used the radio wire for the led strips, my problem is with the led bulbs, not the strips. in other words, the led bulbs are wired into the headlight switch and can be dimmed. The led rgb stips are wired into the radio power and are turned off via a remote. So the LED strips are wired to an outgoing wire from the radio????
Or did you wire them in withe incoming power..and which color wire did you attach these LED strips to???
For sake of trouble shooting I should have not even mention the led rgb led strips as they're turned off and are not part of the problem. When changing over to the led's I installed two led set ups, the led bulbs would be used 90% of the time and the led rgb strips would be used only for effect and were on a separate circuit.
BUT if this seat belt light was not burning dim BEFORE you did this...knowing exactly what you did and where you connected the wires to and to what color wires can make a difference.
I am assuming that "IT" is the seat belt light??????...or is it that the LED's are staying lit????
This type of response is what confuses me due to when dealing with a problem...being extremely clear in what you are communicating... takes any doubt of what you are writing...which helps.
SO if the red led light is NOT installed..does the light stop being dim...which I am assuming is the seat belt light???
DUb
Yes, "it" is referring to the seat belt light only, not all the led lights.
When I remove the led seat belt bulb, there is no bulb therefore it can't be dim. When I reinstall the original bulb it never lights up regardless of whether the seat belt is buckled, the ignition is on/off, or any other option.
Originally Posted by DUB
BUT if this seat belt light was not burning dim BEFORE you did this...knowing exactly what you did and where you connected the wires to and to what color wires can make a difference.
DUB
I recently did a body off restoration as the car sat for 26 years. I don't remember if I had an issue with the seat belt light once the car was complete as I had many other issues to deal with. In other words, I never noticed. I'm going to assume I had this issue before I did the led conversion as the oem bulb would have been installed and it never would have turned on.
Ok, I remember now, I never changed any wiring when I installed the led bulbs as I only removed the oem bulbs and installed the led bulbs so it still operates off of the oem headlight switch as I'm using the oem wiring/sockets.
Yes, the led strips are wired to the radio power wire, but for the purpose of this diagnostics, I've turned the led rgb strips off and they don't connect to the seat belt light, the only light up the gauges therefore it's a totally different circuit which is not in use at the moment. I don't see how the led rgb strips are related to the led bulbs as they're on a totally different circuit and I'm not having problems with them as the don't interfere with the seat belt light at all.
Last edited by Maymyvetteliveforevr; 06-07-2017 at 08:30 PM.
Yes, "it" is referring to the seat belt light only, not all the led lights.
OK...this is where 'mission control' has a problem. I understand that you know some stuff as you put it when dealing with electrical stuff. I get that...and that is fine.
BUT..for whatever it is worth...It is really critical that when you do any conversions or electrical 'what ever's' and have a problem..a very detailed description is required.
In your initial post it kinda reads that you did all the bulbs in LED's if a person wanted to read it that way...or it could read that all you did was the lights for your gauges in red LEd's....becasue it was not clearly written that way with no confusion. And now you stated that not all re LED's...which does make a difference.
Originally Posted by Maymyvetteliveforevr
When I remove the led seat belt bulb, there is no bulb therefore it can't be dim. When I reinstall the original bulb it never lights up regardless of whether the seat belt is buckled, the ignition is on/off, or any other option.
OK...now we are getting somewhere. I did not know you installed an LED for the seat belt bulb. They way I read it was you installed bulbs and now your seat belt warning light bulb is dimly lit. Unless I missed something...which is highly possible.
IF the factory bulb is NOT dim or even working...BUT the LED bulb is dim...then you can have a scenario like was mentioned in one of the past posts that the LED is dim because it takes so little current work...it is dim...but not enough current to make the incandescent bulb shine.
Originally Posted by Maymyvetteliveforevr
I recently did a body off restoration as the car sat for 26 years. I don't remember if I had an issue with the seat belt light once the car was complete as I had many other issues to deal with. In other words, I never noticed. I'm going to assume I had this issue before I did the led conversion as the oem bulb would have been installed and it never would have turned on.
Ok, I remember now, I never changed any wiring when I installed the led bulbs as I only removed the oem bulbs and installed the led bulbs so it still operates off of the oem headlight switch as I'm using the oem wiring/sockets.
I will look at my wiring diagram and if my memory serves me correctly...there is a buzzer that is taped to the dash harness that is a part of the seat belt warning circuit.
Originally Posted by Maymyvetteliveforevr
Yes, the led strips are wired to the radio power wire, but for the purpose of this diagnostics, I've turned the led rgb strips off and they don't connect to the seat belt light, the only light up the gauges therefore it's a totally different circuit which is not in use at the moment. I don't see how the led rgb strips are related to the led bulbs as they're on a totally different circuit and I'm not having problems with them as the don't interfere with the seat belt light at all.
I agree that the LED strips are not a part of the problem.
AS I wrote above....I will look at my diagram and see what is going on.....that is IF you want the seat belt circuit working or not???
First off, thanks for sticking with me on this electrical issue as I know electrical gemlins can be a major pain in the **** which most people don't want to attempt to help out with.
Secondly I apologize for the confusion.
Thirdly, I shouldn't have mentioned the led rgb strips in my initial post as it's totally unrelated to my problem.
This is the statement that describes my problem and thanks for putting in your own words.
I don't believe it will make a difference but in doing the dash and center gauge, I used 4 different led color bulbs, white, blue, green and red. The red is what I used for the "seat belt warning".
Originally Posted by DUB
IF the factory bulb is NOT dim or even working...BUT the LED bulb is dim...then you can have a scenario like was mentioned in one of the past posts that the LED is dim because it takes so little current work...it is dim...but not enough current to make the incandescent bulb shine.
DUB
First off, thanks for sticking with me on this electrical issue as I know electrical gemlins can be a major pain in the **** which most people don't want to attempt to help out with.
Secondly I apologize for the confusion.
Thirdly, I shouldn't have mentioned the led rgb strips in my initial post as it's totally unrelated to my problem.
This is the statement that describes my problem and thanks for putting in your own words.
I don't believe it will make a difference but in doing the dash and center gauge, I used 4 different led color bulbs, white, blue, green and red. The red is what I used for the "seat belt warning".
I think at this stage I'd wire a resistor in series with the bulb in question. The resistor will add a load to thr circuit, more in line with the load a conventional 12 volt bulb would do.
Kinda surprised this hasn't been added to the mix. Those mini leds offer nearly zero resistance, and require so little voltage to light up, a little feedback is all that is required to kick them into gear.
Load the circuit in question then chime in with your thoughts.
At this point, I would get the seat belt warning circuit working with the stock bulb first (do make sure it's good). Then worry about converting it to LED and address any new issues that arise.
At this point, I would get the seat belt warning circuit working with the stock bulb first (do make sure it's good). Then worry about converting it to LED and address any new issues that arise.
You need to get the circuit working with the stock bulb as it should. From what I read, the stock bulb does not light up at all. This means you have a problem with that circuit. The LED for the warning light stays dim regardless of operation, correct? My take is you have a highly resistive grounding happening in that circuit. It is enough that the bulb socket has a constant low voltage regardless of if the seat belt is plugged in or the ignition is on/off. The circuit should have no voltage to it with the ignition off, and should have voltage when the ignition is on plus the seat belt is not connected. My guess would be the relay or warning buzzer switch has shorted, thus leaving you with constant voltage.
05-31-2017, 06:59 AM
Electrical problem with led bulbs in dash.
You need to get the circuit working with the stock bulb as it should. From what I read, the stock bulb does not light up at all. This means you have a problem with that circuit. The LED for the warning light stays dim regardless of operation, correct? My take is you have a highly resistive grounding happening in that circuit. It is enough that the bulb socket has a constant low voltage regardless of if the seat belt is plugged in or the ignition is on/off. The circuit should have no voltage to it with the ignition off, and should have voltage when the ignition is on plus the seat belt is not connected. My guess would be the relay or warning buzzer switch has shorted, thus leaving you with constant voltage.