3rd brake light delete. Procedure, so warning doesnt go on
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From: saratoga, ca
3rd brake light delete. Procedure, so warning doesnt go on
anyone know what it takes to fool the circuit? a 1 ohm resistor? direct short?
I think that is the reason why my brake light warning light is still on and stays on even though the brake lights are working
I think that is the reason why my brake light warning light is still on and stays on even though the brake lights are working
Drifting
Joined: Aug 2003
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From: Camarillo, CA, USA
More than one way.... take a look at this thread...
https://rennlist.com/forums/928-foru...ol-module.html
https://rennlist.com/forums/928-foru...ol-module.html
Electron Wrangler
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From: Phoenix AZ
I would strongly recommend against the direct short...
Swap the lamp control module for one without a central light OR add in an approx 7 ohm resistor (~21 Watt dissipation - so need a bolt down resistor themally connected to a chunk of metal (e.g. inner roof)metal.
Alan
Swap the lamp control module for one without a central light OR add in an approx 7 ohm resistor (~21 Watt dissipation - so need a bolt down resistor themally connected to a chunk of metal (e.g. inner roof)metal.
Alan
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From: saratoga, ca
I would strongly recommend against the direct short...
Swap the lamp control module for one without a central light OR add in an approx 7 ohm resistor (~21 Watt dissipation - so need a bolt down resistor themally connected to a chunk of metal (e.g. inner roof)metal.
you cant swap the lamp controller. its a 14pin version, ('88) vs the older style is 12pin. However, maybe the 87 is still 14pin, but doesnt have this feature? I dont know.
as far as the resistor, is that light over 20watts ? (i.e. 7ohm, drawing over 2 amps) I would think a 10-15ohm resistor could do the trick and I would just use one of those 50watt versions to not worry about the heat sinking to the roof. do you think a direct short at the controller would burn the controller?
Heck, if so, Here is an idea..... why dont i just tap into that circuit and put the light on the dash board so there is a brake light inside for the video.
Alan
Swap the lamp control module for one without a central light OR add in an approx 7 ohm resistor (~21 Watt dissipation - so need a bolt down resistor themally connected to a chunk of metal (e.g. inner roof)metal.
you cant swap the lamp controller. its a 14pin version, ('88) vs the older style is 12pin. However, maybe the 87 is still 14pin, but doesnt have this feature? I dont know.
as far as the resistor, is that light over 20watts ? (i.e. 7ohm, drawing over 2 amps) I would think a 10-15ohm resistor could do the trick and I would just use one of those 50watt versions to not worry about the heat sinking to the roof. do you think a direct short at the controller would burn the controller?
Heck, if so, Here is an idea..... why dont i just tap into that circuit and put the light on the dash board so there is a brake light inside for the video.
Alan
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Mark how about a "brake light" on the dash so your videos will show the exact braking point ? Wire the throttle kick down switch to a green light as well.....I think you had this once before. Or simply add a light bulb anywhere in the roof brake light circuit to make the controller happy.
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From: saratoga, ca
somehow my copied quote reply didnt get posted. Yes, that was one of my options. just running the light the dash for braking lights for the videos. I have the WOT switch light, as well, but that was wired to the kick down switch, which this stick S4 doesnt have.
I cant imagine that the brake light its over 20 watts. I was thinking a 15ohm resistor or something,in the form of one of those 50watt resistors. are the brake lights more than 15 watts each, or is the one on the hatch as much as the one in the tail light section?
that probably is the problem though.
Also, the other part of my response was that the earlier controllers have 12 pin connectors, while this one on the '88 has 14. Unless the '87 has the same 14pin connector, but sans the 3rd light function.
thanks,
Mk
I cant imagine that the brake light its over 20 watts. I was thinking a 15ohm resistor or something,in the form of one of those 50watt resistors. are the brake lights more than 15 watts each, or is the one on the hatch as much as the one in the tail light section?
that probably is the problem though.
Also, the other part of my response was that the earlier controllers have 12 pin connectors, while this one on the '88 has 14. Unless the '87 has the same 14pin connector, but sans the 3rd light function.
thanks,
Mk
Mark how about a "brake light" on the dash so your videos will show the exact braking point ? Wire the throttle kick down switch to a green light as well.....I think you had this once before. Or simply add a light bulb anywhere in the roof brake light circuit to make the controller happy.
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From: Phoenix AZ
Mark when I said ~7 ohms 21Watts - that's EXACTLY what I meant - that why I was specific....
It IS a 21W lamp - as are all 928 brake lamp bulbs - so you probably don't want this on the dash unless its oriented so its not shining in your eyes at all - it will be very bright. You could certainly mount a 21 bulb hidden somewhere else basically as a dummy ballast (in that sense its the same as a resistor) and you could add an LED indicator lamp on the dash wired in parallel.
As to the bulb control unit - I was thinking the ROW cars don't have central brake lamps standard so an ROW bulb control unit would work - however it appears ROW cars still used the 12 pin version (seems odd - but lamp wiring is different enough that I guess the whole rear loom is swapped.) - less easy than I thought... problem.
Alan
It IS a 21W lamp - as are all 928 brake lamp bulbs - so you probably don't want this on the dash unless its oriented so its not shining in your eyes at all - it will be very bright. You could certainly mount a 21 bulb hidden somewhere else basically as a dummy ballast (in that sense its the same as a resistor) and you could add an LED indicator lamp on the dash wired in parallel.
As to the bulb control unit - I was thinking the ROW cars don't have central brake lamps standard so an ROW bulb control unit would work - however it appears ROW cars still used the 12 pin version (seems odd - but lamp wiring is different enough that I guess the whole rear loom is swapped.) - less easy than I thought... problem.
Alan
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Thread Starter
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From: saratoga, ca
Well, if you are trying to be real specific, wouldnt that 7ohms be really, 28watts? (we are talking about a 13.5v system when it runs. ) But, I understand, thanks!
Yes, I dont think I would be putting some brake light in my face. my WOT switch light is a LED as well. I would do something like that.
the real question is if the 87 bulb controller is the same pin out? put it this way, the one that is from 86 chassis is a 12 pin connector that will not fit into the 14 pin connector of the '88. not even close. the question is if the connector change went to 14pin in 87, obviously not supporting the 3rd brake light, or if they changed to this connector in '88. The drawings seem to indicate that the '87s had the 14 pin connector, but who knows if it will work for only the purpose of the 3rd brake light delete.
anyone , anyone?
Mk
) But, I understand, thanks!Yes, I dont think I would be putting some brake light in my face. my WOT switch light is a LED as well. I would do something like that.
the real question is if the 87 bulb controller is the same pin out? put it this way, the one that is from 86 chassis is a 12 pin connector that will not fit into the 14 pin connector of the '88. not even close. the question is if the connector change went to 14pin in 87, obviously not supporting the 3rd brake light, or if they changed to this connector in '88. The drawings seem to indicate that the '87s had the 14 pin connector, but who knows if it will work for only the purpose of the 3rd brake light delete.
anyone , anyone?
Mk
Mark when I said ~7 ohms 21Watts - that's EXACTLY what I meant - that why I was specific....
It IS a 21W lamp - as are all 928 brake lamp bulbs - so you probably don't want this on the dash unless its oriented so its not shining in your eyes at all - it will be very bright. You could certainly mount a 21 bulb hidden somewhere else basically as a dummy ballast (in that sense its the same as a resistor) and you could add an LED indicator lamp on the dash wired in parallel.
As to the bulb control unit - I was thinking the ROW cars don't have central brake lamps standard so an ROW bulb control unit would work - however it appears ROW cars still used the 12 pin version (seems odd - but lamp wiring is different enough that I guess the whole rear loom is swapped.) - less easy than I thought... problem.
Alan
It IS a 21W lamp - as are all 928 brake lamp bulbs - so you probably don't want this on the dash unless its oriented so its not shining in your eyes at all - it will be very bright. You could certainly mount a 21 bulb hidden somewhere else basically as a dummy ballast (in that sense its the same as a resistor) and you could add an LED indicator lamp on the dash wired in parallel.
As to the bulb control unit - I was thinking the ROW cars don't have central brake lamps standard so an ROW bulb control unit would work - however it appears ROW cars still used the 12 pin version (seems odd - but lamp wiring is different enough that I guess the whole rear loom is swapped.) - less easy than I thought... problem.
Alan
