Electrical wiring question

[mrTickle]

Sorry this question isn't bike related but hopefully someone may be able to help me out...

I've just fitted a car alarm into my car. It's working great but I've got a very slight problem. The alarm has one wire coming out of it which sends a +12V pulse when the alarm keyfob is pressed. This 12V wire is meant to be connected into the cars indicators circuit, to give a visual indicator when the alarm button on the keyfob is pressed - the indicators blink twice for arming, once for dis-arming.

I don't have a wiring diagram for my car, so I decided the simplist method was to hook the 12V wire into the cars hazard light switch. The problem I got doing it this way, is that I can only wire the 12V wire into one side of the cars indicators. If I wire it to use use both sides indicators, when the ignition is on and I indicate to turn ( say left ), all 4 of the indicators come on together instead of just the left hand side indicators. Does anyone have any advice on how I can get all the indicators to flash together for the alarm ( maybe using a relay or some other alternative ) and that doesn't make all 4 indicators flash together when I'm indicating which direction I'm turning? Cheers in advance

 

[cookie]

a dual pole relay would do it or maybe you could use a couple of diodes in a "Y" when connecting to both sides of the indicators.



not got the manual for the alarm?

 

[The Mechanic]

Try this....

Without seeing the car its a little difficult, but I think you should be able to isolate the feed wire to the 'hazard' flasher can. This is the wire to link to the pulse wire, so when you arm the system the hazards flash once od twice.

I believe you have probably selected the wrong wire in the hazard circuit.

P.S. its usually a scotch lock 'bodge' connection that the instalation 'experts' normally use.

Good luck.

 

[wessie]

You need to wire into the input side of the hazards relay not the output.

If you know which relay controls the hazards then have a look to see if the manufacturer has printed a wiring diagram on it. If not you need to determine which wire is the switched input. Probably easiest to do at the dash panel switch.

Pull out the hazard flasher switch. Using a multimeter (or bulb with a couple of wires soldered to it) to determine which wire is the switched one. You need to scotchlock into this wire either inside the car or probably easiest in/near the relay housing (hopefully the wire will be a unique colour!)

 

[cookie]

ah!

of course.

 

[mrTickle]

Thanks for the advice guys. I think I'll follow cookie's idea of 2 diodes as it's probably the quickest & easiest solution for me to get this sorted out. Unfortunately the instructions that came with the alarm are rather vague - all they state is that the orange wire must be connected into the indicator circuit - there's no wiring diagram or further explaination whatsoever.

I've had a good poke about in the relay box and to be honest, I don't really know WTF I'm doing in there . There are 8 wires going into the back of the hazard lights switch, and out of that lot I definately know the 2 for the indicators. I'll pop down to Maplins, get meself 2 blocking diodes and scotchlock 'em in.

My next question is what size diodes should I ask for? I've just turned to page 202 of the Maplins catalogue and I'm blowed if I know what a 1N5407 is. If I pop into Maplins and tell tham that I need two diodes for a 12V circuit, running say 6 Amps, do you reckon that would be enough info for them to sort me out?

 

[Fanum]

MrT......Wessie's answer is the winning response..adding diodes and stuff is geting really complicated for no reason......hit the right supply to the hazards and thats the job....

 

[cookie]

MrT......Wessie's answer is the winning response..adding diodes and stuff is geting really complicated for no reason......hit the right supply to the hazards and thats the job....

he's right you know.

if i'd been less idle and looked at a diagram i'd have realised that the 2 sides are probably isolated in the switch.

tapping into the input on the hazard switch is the elegant solution.

 

[Fanum]

Cookie...you aint as cuddly now with that new avatar!!

 

[cookie]

needed a change. going over to the dark side

 

[mrTickle]

I did it with two 50 Volt 6 Amp diodes from Maplins that took me about a minute to connect in. Everything's now working correctly, so cheers for all the help .