Does anyone know where i can find a switched 12v scorce in an lj that stays live when im cranking? and yes ive tried a test light into the back of the switch they all die when cranking.
LJ ignition switch wiring
Started by
_Torana308_
, Feb 13 2006 07:06 PM
9 replies to this topic
#2
_Bomber Watson_
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Posted 13 February 2006 - 08:14 PM
yeah that tends to happen when all the power goes to the starter. you will find that it only dies for the first two seconds or so then comes back on after the innitial surge, even if you keep the starter going. the only way you will eliminate the surge is to run another battery on a seperate circuit.
#3
_devilsadvocate_
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Posted 13 February 2006 - 08:40 PM
The instruments stay live when you are cranking, but only get their power through the resistance wire of the ignition so wont be 12V when cranking. Obviously the wire from the ignition switch to the starter will be live when cranking, but will die when the key is released. You could run a relay where ,trigger wire is connected to the +ve of the coil, this will always give you a switched 12V supply direct from the battery, the reduced voltage on the ign wire in the run position will still be enough to trigger the relay.
More info perhaps, you need the supply to be 12V when cranking and when the engine is running, but switch off when the engine is switched off?
Can I ask the purpose/function, there may be another way to achieve your aim.
More info perhaps, you need the supply to be 12V when cranking and when the engine is running, but switch off when the engine is switched off?
Can I ask the purpose/function, there may be another way to achieve your aim.
Edited by devilsadvocate, 13 February 2006 - 08:48 PM.
#4
_Torana308_
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Posted 13 February 2006 - 09:20 PM
Because i wired the msd up to be switched on and off by a switch but wont pass rwc as car runs with key off until you turn msd off
#5
_devilsadvocate_
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Posted 13 February 2006 - 10:38 PM
Ok, msd is an ignition module/coil?
I take it you will be/are using a full 12v ignition and wont be needing the resistance wire.
In the conventional wiring, the yell wire to the coil provides 12v when cranking and the pink supplies to around 10V when the motor is running.
You really just need to do the basic resistor bypass suggested as in:http://www.gmh-torana.com/index.php?ind=reviews&op=entry_view&iden=7
the module/coil both connecting at the same point.
I take it you will be/are using a full 12v ignition and wont be needing the resistance wire.
In the conventional wiring, the yell wire to the coil provides 12v when cranking and the pink supplies to around 10V when the motor is running.
You really just need to do the basic resistor bypass suggested as in:http://www.gmh-torana.com/index.php?ind=reviews&op=entry_view&iden=7
the module/coil both connecting at the same point.
#6
_Torana308_
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Posted 13 February 2006 - 10:54 PM
problem is my yellow wire goes dead during cranking otherwise id use it
#7
_devilsadvocate_
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Posted 14 February 2006 - 10:07 AM
I see, you can get around that by running a relay using the purple starter wire as a trigger for power from the batt, to your ign device, but do suggest that the best fix would be to fix/replace the ignition switch - check that the yell wire is connected at the other end
#8
antelopeslr5000
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Posted 16 February 2006 - 06:51 PM
OK, I'll ask the stupid question here...
What is the purpose of switching the MSD on and off with a switch? Why wouldn't you want it to switch off when the ignition is switched off?
When you switch the MSD off, does that by-pass the MSD igintion system and the car reverts back to a normal ignition system? I guess I can see some logic in that setup (for redundancy purposes). If the MSD should fail for some reason then you can by-pass it and still be able to drive your car.
Oh yeah, nearly forgot to mention. DON'T connect anything to the +ve side of the coil if your running an MSD. Connect only the orange wire from the MSD. That's because the MSD has an output near 450 volts, not 12 volts.
Sorry for all the questions!
What is the purpose of switching the MSD on and off with a switch? Why wouldn't you want it to switch off when the ignition is switched off?
When you switch the MSD off, does that by-pass the MSD igintion system and the car reverts back to a normal ignition system? I guess I can see some logic in that setup (for redundancy purposes). If the MSD should fail for some reason then you can by-pass it and still be able to drive your car.
Oh yeah, nearly forgot to mention. DON'T connect anything to the +ve side of the coil if your running an MSD. Connect only the orange wire from the MSD. That's because the MSD has an output near 450 volts, not 12 volts.
Sorry for all the questions!
#9
_Torana308_
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Posted 16 February 2006 - 07:35 PM
all solved found the right wire to use and all works properly now thanks for the help. The switching was because i couldnt find a feed that stayed live while cranking so no ignition and no start so had to use a permenant 12 v to keep it working while cranking
#10
antelopeslr5000
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Posted 16 February 2006 - 08:42 PM
Good to hear!
I wasn't sure exactly what you where trying to achieve.
I used the 12 volt (pink wire ?) which was originally attached to the +ve side of the coil before the MSD installation. Connected that to the red wire of the MSD (not the heavy gauge red wire of course!).
I wasn't sure exactly what you where trying to achieve.
I used the 12 volt (pink wire ?) which was originally attached to the +ve side of the coil before the MSD installation. Connected that to the red wire of the MSD (not the heavy gauge red wire of course!).
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