Corner light DRLs
Technical Article Contributor
Joined: Jun 2002
Posts: 10,511
Likes: 10
From: Under the flightpath of old ORD 22R
Connecting the 2 powers together ( the one from the hot in the run position of the key and the parking lamps themselves ) is no big deal.
The problem becomes circuit 14 ( Brown ) parking lamps seems to the the same circuit and wire ( via a few splices ) as the rear tail lamps.
This would require a Diode on each wire from the Circuit #14, towards the bulb connector. The Cathod ( side of the Diode with the line on it ) on the bulb connector side, the annode towards the factory harness.
The cathod needs to be nore negative then the annode side for current to flow. The circuit #14 finds ground via the bulb element, which means the bulb direction is more negative ( towards ground ) then the factory harness side.
When the Hot in run postion circuit is connected between the diode and bulb connector, the more negative side is still towards the bulb connector, which means the current will not flow back. That is what I draw out on paper, thinking it out.
This will stop the voltage from the hot in the run position from feeding back through the truck harness and illuminating the rear tails ( and maybe the instrument cluster..I did not look and see if that is the same circuit #14 or not ).
The Right side hot in run postion is only connected to the circuit #14, between the bulb and diode, I just saw I drew it across the ground circuit, without the little half circle ( showing no connection ). Sorry about that.
The unknown questions :
1. What size diode? It has to be able to handle the AMP draw of the front parking lamp, which I think is a standard 5 Watt.
2. There will be a voltage drop across the diode, causing the parking lamp to burn dimmer when the headlamp switch is in the parking lamp or headlamp postion. This might be a very slight difference, depending on the resistance of the Diode when compared to the bulb. Example is if the diode and the bulb element have the same resistance, the voltage drop over each ( bulb element and the diode ) will be the same, meaning the parking lamp will be half as bright when the headlamps are on.
3. Did I recall electronics 101 correctly from college in the 1980's ?
I don't use this stuff that often...
4. Source for the diode ? Stereo shop maybe ??? Don't know if they would carry this or not. A test with wire and a LED would prove it out, prior to finding the parts. Just don't try to run this with a small LED, it will go poof, and you know the saying, electronic run on smoke, once you release the smoke, they don't work anymore.
No problem with the assist, I am glad I just got my head around what you were looking for function wise, prior to having you hack up your factory harness.
The problem becomes circuit 14 ( Brown ) parking lamps seems to the the same circuit and wire ( via a few splices ) as the rear tail lamps.
This would require a Diode on each wire from the Circuit #14, towards the bulb connector. The Cathod ( side of the Diode with the line on it ) on the bulb connector side, the annode towards the factory harness.
The cathod needs to be nore negative then the annode side for current to flow. The circuit #14 finds ground via the bulb element, which means the bulb direction is more negative ( towards ground ) then the factory harness side.
When the Hot in run postion circuit is connected between the diode and bulb connector, the more negative side is still towards the bulb connector, which means the current will not flow back. That is what I draw out on paper, thinking it out.
This will stop the voltage from the hot in the run position from feeding back through the truck harness and illuminating the rear tails ( and maybe the instrument cluster..I did not look and see if that is the same circuit #14 or not ).
The Right side hot in run postion is only connected to the circuit #14, between the bulb and diode, I just saw I drew it across the ground circuit, without the little half circle ( showing no connection ). Sorry about that.
The unknown questions :
1. What size diode? It has to be able to handle the AMP draw of the front parking lamp, which I think is a standard 5 Watt.
2. There will be a voltage drop across the diode, causing the parking lamp to burn dimmer when the headlamp switch is in the parking lamp or headlamp postion. This might be a very slight difference, depending on the resistance of the Diode when compared to the bulb. Example is if the diode and the bulb element have the same resistance, the voltage drop over each ( bulb element and the diode ) will be the same, meaning the parking lamp will be half as bright when the headlamps are on.
3. Did I recall electronics 101 correctly from college in the 1980's ?
I don't use this stuff that often...4. Source for the diode ? Stereo shop maybe ??? Don't know if they would carry this or not. A test with wire and a LED would prove it out, prior to finding the parts. Just don't try to run this with a small LED, it will go poof, and you know the saying, electronic run on smoke, once you release the smoke, they don't work anymore.
No problem with the assist, I am glad I just got my head around what you were looking for function wise, prior to having you hack up your factory harness.