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Fog lights as fog lights and brake lights. (How to set your car on fire) 700

Below is a request for comments. It is also a repeat for those of you who read ALL in RWD. I'm reposting specifically to the 700 fans in the audience, since this is my target platform. If someone thinks the 200 crowd would dig it, then repost it yourself or tell me to repost it and I will. It sure would be nice (*looking at jarrod*) if the dropbox system was redone with checkboxes.

I just got back in from doing another stupid electrical trick. In my wagon, I have negated the fog light switch and spliced the rear fogs streight into the brake lights. This is my affirmation that doubling the brake light load won't burn up the wire harness [immediately].

As an improvement for my sedan, I decided to jumper a diode in the correct polarity between the brake light line and the rear fog light line. This has the effect of using the rear fog lights as brake lights when they are not being used as fog lights. When they are used as fog lights, they do not interfere with the brake lights. Since the fog light line does not appear to be 'isolated' in any way, connecting the diode on ONE side lights both fogs, as well as both indicators on the dash.

I am not sure of the ramifications for the bulb failure warning relay, although I would imagine that during a rear fog light failure, it would come on when the brakes are applied, or when the rear fog lights are applied.

I posted this to all even though I'm talking about a 700 series because it likely applies to 900's and 200's.

#### UPDATE ####
The described above effect of turning on the dash indicators has a possible bad side effect. As would be expected, the dash lights (the one on the switch, and the idiot light) come on when the key is out and the brakes are depressed.

Where the undesirable effects come into play is when the car is off, the rear fog switch is in the on position, and the brakes are depressed. This causes power to be supplied to the circuits that power the rear fog lights, which appears to cascade upward to most systems.

The fix for this will require inserting another diode between the rear fog switch and the rear fog light. This could be done at the tail light (which would quadruple the numbr of diodes needed) end, or more likely under the dash.

Any suggestions would be nice. :)
--
89 760 GLE 150k/ 86 740 GLE 240k -- Still going.






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New Fog lights as fog lights and brake lights. (How to set your car on fire) [700]
posted by  cancerman  on Tue Jan 29 14:15 CST 2002 >


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