Battery Drain from LED’s, Scanner

Hello all,     I own a 2001 civic with a solaris. I currently have the normal red led running along with a varad EL501, electrolum...scanner. I put the windshield washer leds in a while back but since they are illegal to drive with i never run them. What i was wondering is if i could hook them up and run all three of these theft deterrent devices without draining my battery if left on for a significant amount of time. This is how i belive i would hook up the leds to flash, i thought it would be cool if I alternated them. Please correct me if i am wrong in my diagram. Relay #1 30: 12v fused 86: 12v fused 85: (-) out from alarm when armed 87: 12v out to other relay Relay #2 30: 12v when armed (from 87 of other relay) 85: 12v ""                 "" 86: (-) flashing output from alarm led 87: 12v output to one washer led 87a: 12v output to other washer led Ok, i'm assuming this would all work. Let me know if there are any flaws and if it is ok to trip a relay so much, cuz it would be on and constantly switching as long as my alarm is armed. And...an educated guess as to how long my battery would last running all of these acc's. I know by themselves they take minimal power but all combined they have to amount for something right? Anyway thank you so much you guys for all your help. I have learned so much just from cruising this forum and being corrected when wrong. Thanks!

i dont think the combined led's would drain your battery, but energizing the relays might...

Not exactly a good idea, first of all, most LED(including the blue and superbright) doesn't take 12V input unless you want to blow them up. Second is, Since normal alarm LED is running off 1.5-3V, hooking up that 12V accross 85 and 86 on your 2nd relay probably will fry your circuit on your alarm since you're putting 12V into the ground that designed only for pulling 1.5V. Even though the whole concept work, are you really sure you want your car go clicking like a time bomb whenever you arm the car? :) Afterall if you really want to flash your LED like that when you arm your car, the best way to go is build a timming circuit (or find one on the internet) for that purpose only. Hope that helps.

I prefer to have two leds at the most.  "low profile."

Hey thanks guys,    That answered my question, i figured that the realy would give me grief if always on. So how much juice do they pull anyway? I am asking because i bought a 450t channel expander and am wiring it up to the aux channel on the solaris. I don't want any of the aux channels to work if the car was armed so i was going to interrupt the signal using a relay, triggered by the ground when armed. let me know if this would work or is a good idea: 30: alarm side of (-) auxillary channel 87a: 450t side of (-) aux channel 85: 12v 86: ground when armed This in theory would disconnect the aux channel from sending a signal to my channel expander when the car is armed. Alrighty, let me know if this is a wise thing to do, or if i can just set my solaris to only output the aux channel when disarmed. Thanks a ton! spart

A typical 5-terminal relay like your describing draws about 1/4 amp when active. If it were me trying to do multiple LED's on one output I would use a grounded output to supply the negative side of a simple 555 timer circuit to flash two alternating LED's. The 5 volt supply to power the 555 can be acheived with a voltage regulator (transistor).  The transistor and 555 timer are extremely small and cheap. I would think you could build this circuit for under $5.00 easily. If you want to give it a try and need some help, email me at mikelin4@hotmail.com

Your right, a 555 timer can be powered by a 12V supply. Be sure to get one that is rated for this. Some models work only off voltages as low as 3 volts. The transistor idea is a good idea as well. That circuit will blink all LED's at the same time rather than alternate however. Here is a simple circuit that will do just what you want it to if you choose to use the 555 timer. This circuit uses 6V (the 5 volt regulator will work fine) if you want to connect it directly to 12V you will need to change a resistor value.