Great explanation, thanks! I went to electronic school 30years ago, but since I don’t work in the field anymore, it’s terrific to get a refresher now and then. This was explained perfectly!
This is exactly what I needed to remember how to use diodes! I'm trying to use the headlight load on a dual beam lamp (H4) so that my aux. stays powered regardless of if the low or high beam lamps are on. Diodes are required.
Ive watched alooooot videos, and just as i was about to go sleep i said to my girl, the elderly guys are better at explaining stuffs in the simplest of way, i can get on wit my project now ....Thank you!
Great example and wonderful explaination! Could you also recommend some good automotive diode, for common use cases? I'm looking for models that can take like 4-5A, and shouldn't drop much voltage. Thanks!
Thanks for your video, very interesting. Let me share with you about a project I'm doing, hoping you can help me. I have installed coloured LED lights on the door of my volvo xc60 and have a bluetooth controller to control or change of lights from an app. Power is taken from the windows circuit. Without the controller (bluetooth controller), everything works properly, although I can't control the lights, but with the controller, when I speed up, the window goes up. Any sugestion?
Thank you, I am looking at wiring a backup camera to my vehicle so that it turns on with my reverse lights and turns on with a switch on the dash. Great explanation!
Nice , is this still possible with a shift function button , to another button across more than 2 loads , without using 2 pole switches ? Example , shift button , plus button 1 = load 1 , Shift button plus button 2 = load 2 . Normal use , button 1 = other use , shift plus button 1 = load 1 . Wanted use , extra button , enable shift and button 1 = load 1 , using one pole switch to do both shift and button 1 = load 1 , I can get working , 1 button , but adding extra button after creates all buttons = load 1 . ??
very useful, thanks. how do we know what diode do we need there? since, for example, for a fan we need very much amps? what kind of diode should we use if there's a 500A draw?
I am a complete beginner on electrical circuits. Very tough to understand these circuits. I understand how in this example a parallel circuit uses diodes to prevent unwanted current paths. But the more I think about the example it looks to me like you would need 4 diodes to make this circuit work correctly. With 2 diodes as shown it looks like current would/could still flow backwards on the aft sides of the loads instead of the forward side of the loads. Im further confused by the concept that electricity is lazy and flows 100% on the path of least resistance to ground. That would mean all the current flows on the easiest side of a parrallel circuit? If that is true all the current would flow through the bulb straight to ground and neither load would get current regardless. Can anyone help explain these confusions?
Can taking out one and swapping it with a new on with the key on can it burn up the diode? Or mess up the pcm? I had to have the key one to test some fuses..I forgot to turn the key off before I swapped the diode
Great, informative video. 2 thumbs up! I'm about to install auxiliary backup lamps in rear bumper of my old pickup (36W each or ~6 Amps). I want them to get power when the OEM backup light switch is on (when in reverse gear with engine running) OR when a dashboard switch is on; so I will splice the wiring somewhere after the OEM backup light switch to feed a relay at terminal 86. I want the dashboard switch so I can have lights when the truck is not running. I plan to run a wire from the battery (fused at 10 amps) to a relay. Both the wire from the OEM backup light switch and the wire from the dashboard switch will feed the relay terminal 86 and the hot wire will feed the relay terminal 30. Relay terminal 85 will go to ground and terminal 87 will feed power to the lights. I do not want the OEM backup lights in the taillight assembly on if the engine is not running. To prevent that, I plan to use a diode in the wiring from the OEM backup light switch. Does this plan reflect a correct understanding of using a diode? How do I size this diode?
To size a diode you need to know the amperage that will be pulled through the circuit when the load (lamps) are running through the diode. Don't want one too small or it can burn up. That said using a relay your load should never go through the diode anyway as you load will be direct battery voltage to the load side when the relay closes. Your diodes will be on the signal wires that activate (close) the relay when they are powered and there is really no load on those, other than the relay coil. I did something like this to power my lightbar on my UTV. I wanted it to be able to be switched on with key in ACC position AND running. That mean I needed 2 switch wires coming in, each needed a diode. I used 15A diodes, worked fine
@RPG123 I think what he means is he wants to be able to turn on the aftermarket lights in the bumper without the OEM reverse lights illuminating as well when he engages the switch for like a manual override. So in that case, when he puts 12v on pin 86 (I think) via dashboard switch, that would also put 12v on the OEM reverse bulbs and light those up as well. But yes, I agree and think 15 amp rated diode would work great.
@@1windozesuk Thanks for your post. Yes, that is exactly what I want to do and the diode is to keep the OEM reverse lights from coming on when the dashboard switch is closed. Now I know what diode to use. (I'm past 80 so these projects take a very long time :) )
@@rhhutchins194 I'm a little more than halfway there myself and they take me about that long too! Especially anything under the truck. I just did my rear bumper and it was an aftermarket with LED pods in it. I didn't use a diode (I didn't think of it), what I did was used a relay triggered by reverse lights that closes a ground running into the cab and that closes another relay in cab that provides 12v from battery in cab for backup camera and future use for things I may need later. Then I have that 12v trigger another relay in cab to close a ground running back to the bumper with yet another relay at bumper connected to a 10awg 12v power wire I ran for trailer plug to turn in the aftermarket LED in bumper. I have a 3 position (SPDT) switch (and more relays in cab) so I can set the LEDs to turn in with reverse lights, manual override or completely off. I probably should have used a diode and less relays. O well.
hi could i use this to controll one buzzer for indcators on a car so that when you indcate right the left indcator does not work as well and could you show how to work out the correct size of diodes for the load thanks
Great Video. I do have one question. If you want to protect this circuit with a fuse, Where would it be placed? Is the diode preventing the fuse to do it's job if a short occurs before the lights?
@@JulianEdgar Sr. Are you for hire? I have a question on how to prevent a 12v current back feed when using two power supply to power some L.E.D strips. I just do not what to be abusive of your time and knowledge.
80s GM/Opel do notg have reverse protection on voltage stabiliser,delco12si do not have diodes,dual relay effects acure,and xenon do not have ballast as well recepi for desaster car self acelerates and engine works with key off basicali not to mention buzzing or stuck horns so relays and zener diodes who are not existing in my hei cause lot havoc normali clamping zener diode shuld by on the 4 pin gm ignition module so not to mention coolant electrolisys .I can only sugest cloosed loop systems insted and to use pureli wires insted of ground chassys as negative conection . And dual baterry system or baterry /capacitor banks and use magnet alternators insted. The normal parts cause to much havoc some are usefull like more power and bether economi but at same time static causes gages to malfunction ! Those are Gasoline-Disel Blocks they are tricky to tune but work well even with back fead how ever the baterry does not like it!
