camerondownunder88 Posted November 17, 2007 Report Share Posted November 17, 2007 (edited) Hi, I am planning to start installing a thermo fan into my KE15 very soon But am just wondering which is the best way to take the ignition feed from. The Thermo fan loom has a main power feed from the battery But it also takes power from a wire that is live when ignition is on so the thermo fan is only on when the car is on. Now I got out my KE15 wiring loom schematic and looked at it and though the best place to take a power feed from would be the ignition barrel. The feed only needs low amps as it is the switching power for the relay so the wires connecting the ignition barrel will handle the draw. But now here is where I'm stuck. On the back of the barrel there are 4 wires. Labeled as follows: ST AMM IG ACC Now ACC is obviously accessories, IG is ignition, and ST is start. But what does AMM stand for? From my point of view I think the wire which is IG would be the best one to tap off as it is where the key will sit when the car is running so it is the ON position. But does anyone know of a better wire to jump in a KE1X car if the IG one on the key barrel isn't the best?? If possible id like a live wire that is inside the engine bay so it saves getting a wire though the fire wall. Cheers Cameron Edited November 17, 2007 by camerondownunder88 Quote Link to comment Share on other sites More sharing options...
Clapped out Posted November 17, 2007 Report Share Posted November 17, 2007 (edited) Just an idea fella, if you only need IG power to enguage the fan relay, you could always use the IG wire that powers the coil? its the only one i can think of in the engine bay. Ive used the IG coil wire (the one that comes out of the harness to power the coil) to run my fuel pump in a similar way, i still have the wire running directly from the harness to the coil and have just run a wire from the coil to the accessory I'm running (if that makes sense?), by doing this it hasnt dropped the voltage to the dizzy. As long as its to only enguage the relay and not power the fan. as for the AMM...............................? cheers phatke30! Edited November 17, 2007 by phatke30 Quote Link to comment Share on other sites More sharing options...
camerondownunder88 Posted November 17, 2007 Author Report Share Posted November 17, 2007 Cheers phatke30, I was a bit iffy about the coil power feed with would it draw to much, or would there be power transients there that would affect operation of the relay etc. But if you have done it so will I :lolcry: As it is just switching the relay so no real big power draw. As for the AMM wire on the back of the ignition barrel. I looked and followed through all the wires on all my different KE1X series electrical diagrams and in the Toyota factory ones they put this HUGE label for a part on top of the inter section for all of the ignition barrel wires. So in turn you don't know which ones goes in which direction..LOL But I did further investigation in my parts manuals for KE1X cars and in there it list all the wire plugs used what wire they attach to and where they plug in. Now for the key barrel it list IG ignition plug, ACC accessories plug. AMM it just says ignition also. So I am thinking this is more of an unmarked wire so it is possibly the one you would jump to "hot wire" the car?? Cheers Cameron Quote Link to comment Share on other sites More sharing options...
KE30_KE35_KE55 Posted November 17, 2007 Report Share Posted November 17, 2007 Cheers phatke30, I was a bit iffy about the coil power feed with would it draw to much, or would there be power transients there that would affect operation of the relay etc. But if you have done it so will I :lolcry: As it is just switching the relay so no real big power draw. As for the AMM wire on the back of the ignition barrel. I looked and followed through all the wires on all my different KE1X series electrical diagrams and in the Toyota factory ones they put this HUGE label for a part on top of the inter section for all of the ignition barrel wires. So in turn you don't know which ones goes in which direction..LOL But I did further investigation in my parts manuals for KE1X cars and in there it list all the wire plugs used what wire they attach to and where they plug in. Now for the key barrel it list IG ignition plug, ACC accessories plug. AMM it just says ignition also. So I am thinking this is more of an unmarked wire so it is possibly the one you would jump to "hot wire" the car?? Cheers Cameron I would run a relay to power the fan straight from the battery with a in line fuse holder, switch the relay with horn, wiper,or accessory's circuit so if something goes wrong and you blow a fuse you want be stuck without ignition. some ignition systems use a 8v volt coil with either a ballist resistor or high resistance wire in the loom. The AMM may give a 12 volt boost to the coil whilst cranking, some starters also have a pin that can be used to boost the coil whilst cranking. in any event I would not take power from the coil, I have seen some LPG installers do it and they run their solenoids off 8 volt. Quote Link to comment Share on other sites More sharing options...
ca18rolla Posted November 18, 2007 Report Share Posted November 18, 2007 I would be installing a temp sender/switch in a radaitor hose or put a fitting in the radiator tank so that the thermo only swicthes on when needed. Otherwise its constatly on. This would take your car longer to warm up and will be on when not needed such as driving on the freeway etc. It is also bad as you want a certain temp in the cooling system. The ideal for my ca is 93 degress. So i have a switch i think ranges from 90-95 degress (Oil is at the right temp, fuel vauporizes properly etc) Quote Link to comment Share on other sites More sharing options...
KE30_KE35_KE55 Posted November 18, 2007 Report Share Posted November 18, 2007 I would be installing a temp sender/switch in a radaitor hose or put a fitting in the radiator tank so that the thermo only swicthes on when needed. Otherwise its constatly on. This would take your car longer to warm up and will be on when not needed such as driving on the freeway etc. It is also bad as you want a certain temp in the cooling system. The ideal for my ca is 93 degress. So i have a switch i think ranges from 90-95 degress (Oil is at the right temp, fuel vauporizes properly etc) Yes of corse you need a thermostatic switch, The two power sources are simply so the fan switchs off when the car does. Quote Link to comment Share on other sites More sharing options...
camerondownunder88 Posted November 18, 2007 Author Report Share Posted November 18, 2007 Hi, KE30_KE35_KE55 I don know what you mean. All KE30 and newer cars run on 8V to the coil. I got my Ohm meter out and measured my coil + today and got 12V+ on it so I know I shouldn't have a issue there. But I will hunt around for another power feed in the engine bay area that is only on when running so the fan wont constantly have power and run when the car is off and still warm. But I am not actually running the fan from the 12V+ signal I am looking for and asking about in this thread. I probably should of mentioned this earlier in first post that I am using a Davis Craig thermo switch to operate this fan. I have the temp probe in the top radiator hose and I will set the temp just right when I get the KE15 going. So the power feed I am looking for in this thread switches the relay I have that then turns the fan on and the main power feed for the fan to the relay is 12V+ from the battery. So the feed I'm looking for is simply a small power feed that is on when the car is running only so I can switch the fan circuit on. Cheers Cameron Quote Link to comment Share on other sites More sharing options...
KE30_KE35_KE55 Posted November 18, 2007 Report Share Posted November 18, 2007 (edited) Hi, KE30_KE35_KE55 I don know what you mean. All KE30 and newer cars run on 8V to the coil. I got my Ohm meter out and measured my coil + today and got 12V+ on it so I know I shouldn't have a issue there. But I will hunt around for another power feed in the engine bay area that is only on when running so the fan wont constantly have power and run when the car is off and still warm. But I am not actually running the fan from the 12V+ signal I am looking for and asking about in this thread. I probably should of mentioned this earlier in first post that I am using a Davis Craig thermo switch to operate this fan. I have the temp probe in the top radiator hose and I will set the temp just right when I get the KE15 going. So the power feed I am looking for in this thread switches the relay I have that then turns the fan on and the main power feed for the fan to the relay is 12V+ from the battery. So the feed I'm looking for is simply a small power feed that is on when the car is running only so I can switch the fan circuit on. Cheers Cameron If you want good starting you need to give full voltage to the coil. it has a certain size wire if you start pulling extra current off that wire the voltage will drop. you may notice less performance or starting problems. the ignition is also on a fuse if something goes wrong with your thermo fan circuit you don't want your ignition cutting out, if it is hooked up to say a horn circuit and it blows a fuse then it really does not matter. Edited November 18, 2007 by KE30_KE35_KE55 Quote Link to comment Share on other sites More sharing options...
Trev Posted November 18, 2007 Report Share Posted November 18, 2007 Where did my post go? Quote Link to comment Share on other sites More sharing options...
MRMOPARMAN Posted November 18, 2007 Report Share Posted November 18, 2007 the switching side of a relay needs very little voltage to close the circuit. so you shouldnt have any problems with starting/running etc. id also be running a seperate switch to either send power/earth it out incase of circuit failure. ill post up a picture of my setup when i work out how to use photoshop. i actually use ign feed off the coil also :lolcry: Quote Link to comment Share on other sites More sharing options...
camerondownunder88 Posted November 18, 2007 Author Report Share Posted November 18, 2007 Just use MS Paint much easier..lol Quote Link to comment Share on other sites More sharing options...
tojo2 Posted November 18, 2007 Report Share Posted November 18, 2007 On ke30s there are 2 12v feed lines to the coils. One comes from "start" on ignition switch and goes directly to primary side of coil. The other one comes from "ig" on ignitonswitch and goes via the coil resistor and becomes 8v on the coil primary. This is why you get higher voltage on coil while starting. Take a look at your voltage regulator. I think there is a connection called "ig" on it . You can use this to feed your fan relay. Its fused aswell, so better than the coil feed. Would be interesting to see the el.drawing of the ke15... Quote Link to comment Share on other sites More sharing options...
KE30_KE35_KE55 Posted November 18, 2007 Report Share Posted November 18, 2007 (edited) On ke30s there are 2 12v feed lines to the coils. One comes from "start" on ignition switch and goes directly to primary side of coil. The other one comes from "ig" on ignitonswitch and goes via the coil resistor and becomes 8v on the coil primary. This is why you get higher voltage on coil while starting. Take a look at your voltage regulator. I think there is a connection called "ig" on it . You can use this to feed your fan relay. Its fused aswell, so better than the coil feed. Would be interesting to see the el.drawing of the ke15... The KE1X Is A 12 Volt system, but your voltage regulator idea is very good. Edited November 18, 2007 by KE30_KE35_KE55 Quote Link to comment Share on other sites More sharing options...
Felix Posted November 19, 2007 Report Share Posted November 19, 2007 (edited) My ke16 had a davies craig thermo fan on it when I go it. It had the the ignition feed wired from the coil to the relay. It was running an electronic dizzy (with bosch transistor coil) and never had any starting issues whatsoever. The power draw to feed the thermo relay was negligable, as I measured the spark voltage at 30,000 volts at idle with and without the fan running. Compare that to my ke15 with an echlin gx80 sports coil, jaycar HEI and scorcher points dizzy at 25,000 volts. KE1x cars run non-ballast coils. Edited November 19, 2007 by Felix Quote Link to comment Share on other sites More sharing options...
ca18rolla Posted November 19, 2007 Report Share Posted November 19, 2007 Yes of corse you need a thermostatic switch, The two power sources are simply so the fan switchs off when the car does. " Yes of course" seen so many people that don't though!!!!!! JUst stating a point that not everyone knows Quote Link to comment Share on other sites More sharing options...
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