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Yeah that sucker is strange. I tried to putting in a LED for the Dash in there but it blew it out instantly.

It's 12 volts but for some reason it will not take a LED.

Didn't the Brits use the same color wire in their cars years ago?

Jim,
The source voltage to operate an LED is typically around 2.5 volts. It will burn out @ 12, thus the need for a resistor in the circuit. More here:

LED circuit - Wikipedia, the free encyclopedia

However, there are LEDs designed for 12VDC automotive applications:
www.vishay.com/docs/83099/tlrp4900cu.pdf

Sherwood

Hey Sherwood, Happy 4th!

http://www.superbrightleds.com/cgi-bin/store/index.cgi?action=DispPage&category=755&Page2Disp=% 2Fspecs%2Fba7s.htm

Well, stange. I got the LED bulbs from SuperBrightLEDs for my dash (supposed already built in resistor) before I installed the EL WIRES. They never blew in the gauges.

I figured since they were the same OD and shared the same Black/Blue hot lead it would just be a plug and play. Doh, NOT!

So if I, install a resistor to that end, it may work, but How will effect the down stream to the gauges? I have the El Wire hooked up to the EL Wire Transformer, I hate for that to be effected.

over,

The electrical engineers were trained at the same school as the AC engineers before 1990s.

Quote:

Originally Posted by nineball (Post 6113809)

i have, and almost had one. the power wire for the ashtray light was so old the casing was brittle and started flaking off. one day after starting the car the cabin filled with so much smoke i could not see out the window and the culprit was the ashtray lighter wire grounding out. a simple fuse would have prevented the smoke, and my almost heart attach, from happening.

THIS reminds me that I need to revisit that ashtray circuit.....I've long (ago) fused the interior lights at the switch (common mod) but something tells me I recalled the ashtray circuit to not be included in that mod,..of course, I could be wrong...I think I may want to verify that glove box light, as well.

BEST!

Doyle

Quote:

Originally Posted by DRACO A5OG (Post 6114794)

Hey Sherwood, Happy 4th!

BA7s LED Bulbs Specifications

Well, stange. I got the LED bulbs from SuperBrightLEDs for my dash (supposed already built in resistor) before I installed the EL WIRES. They never blew in the gauges.

I figured since they were the same OD and shared the same Black/Blue hot lead it would just be a plug and play. Doh, NOT!

So if I, install a resistor to that end, it may work, but How will effect the down stream to the gauges? I have the El Wire hooked up to the EL Wire Transformer, I hate for that to be effected.

over,

You too Jim,
Each gauge bulb holder is wired in parallel with the main gauge light source wire. Thus, you could connect the appropriate resistor in each branch circuit and be good. However, aren't these specific bulbs designed to work in this application as is and w/o an external resistor?

What loads are downstream of the gauge lights? If so, they would also be affected by the dimmer switch (which, btw, should be in the "fully bright" position for the LEDs to operate at their specified voltage).

Sherwood

Yes, these LED bulbs were designed for 12V source with supposed built in resistors.

Up Stream would be the gauge, vent/heater levers, Display knobs for the Fog and Defroster and center console heat lever display.

Actually these LEDs dims along with the OEM dimmer.

I am thinking maybe this is the only socket that is not grounded?

In the late 1970's my '73 914 burned the wire from the fusebox to the highbeam indicator; the whole length. For no good reason I could find. The replacement wire was fused by me.