rayaapp2 Posted November 1, 2009 Share Posted November 1, 2009 (edited) So Ive discovered something new about the starting circuit in my Z. Its obvious now, but I didnt realize it until I installed my turbo timer. I have a 74 which for all purposes has been setup like a 240Z. So no more inhibitor system or any of that non-sense. After the Turbo timer was installed the car engages the starter when the key is put to the lock position to be pulled out. I fused with the wiring for about an hour before realizing the ignition switch spins about 210 deg from its locked position. This means there is a point where the starter contacts pass each other before the "garage" or "off" position is reached and then the circuit is powered up and the contacts are engaged at the start position. So if we leave everything powered up and bypass the ignition switch then when we sweep past the "garage" or "off" position and turn towards the "lock" position again the starter circuit which is still powered up is completed and the starter is engaged. Hopefully that makes sense. I know what the problems is now. The question is, IS there an elegant and simple solution to this? How can I make both these systems work together without this interference and still retain a stock look? Im not wanting to install a switch that has to be flipped or something like that. My wife drives the car, so it has to be easy. Maybe a relay or something. My brain is a little fried at the moment. Ray EDIT LOOK its 5 year old problem!! http://forums.hybridz.org/showthread.php?t=90203 BTW, Ive bought from Japandy as well. Very favorable experiences in the past. I bought my current unit NEW. APEXi unit. Its not the units fault nor the seller. Its our cars. The Ignition switch circuits were not designed to be doing what we are doing to them. I would venture a guess that any of the models with a similar ignition switch... 240Z, 260Z, 280Z, 280zx, and Z31 would all suffer from this same problem. Newer ignitions may also as I have some 90's SX and Q45 units that look like a similar setup. Edited November 1, 2009 by rayaapp2 was searching and found this problem is 5 years old at least Quote Link to comment Share on other sites More sharing options...
rayaapp2 Posted November 2, 2009 Author Share Posted November 2, 2009 (edited) http://www.zcar.com/forums/read/1/478530/478530#msg-478530 "there must be a diode in the adapter harness to prevent a backfeed through the circuit board re-engaging the starter..." Tony D May be a step in the correct direction Edited November 2, 2009 by rayaapp2 picture added for aid Quote Link to comment Share on other sites More sharing options...
eec564 Posted November 2, 2009 Share Posted November 2, 2009 What you need is a turbo timer with anti-grind. Or just build an anti-grind circuit. Systems with remote start capabilities nearly always have this built in, so when you put the key in and accidentally turn the key too far you don't ruin your starter motor. Rather than simply tapping in to the ignition wire and keeping it on for a specified amount of time, the system taps into main power, ignition power, and intercepts the starter signal from the key. You actually cut your starter wire in the same way as you install a starter kill for an alarm. My remote start is actually part of my alarm, so the anti-grind function is the same as the starter kill, except the alarm has the capability to start the car after isolating the starter switch. You can build this circuit in to a turbo timer system fairly easily, with a single relay (preferably a starter kill relay, as they have 40 amp rated NC contacts and come with a heavy duty socket/harness) and a diode. Actual requirements will vary depending on specific installation (turbo timer used, other modifications to the car) and the current requirement of the ignition circuit. -Eric Quote Link to comment Share on other sites More sharing options...
rayaapp2 Posted November 2, 2009 Author Share Posted November 2, 2009 (edited) Ill do some research on an "anti-grind" circuit. Can you fill me in a bit more of how it might be built? Personally I have set my starter circuit up on a relay already. I isolated the starter circuit on the car to kick a relay. This protects the ECU "start" circuit as I have a swap. So the solenoid isnt connected in anyway to the ECU, though I should have installed a diode as well... same thing with the fuel pump relay. So I may be half way there already. Thanks for the GREAT start! Im not sure how this could be implemented. Edited November 2, 2009 by rayaapp2 yes that is APEXi diagram that says "PERKING" Quote Link to comment Share on other sites More sharing options...
eec564 Posted November 2, 2009 Share Posted November 2, 2009 I can try to fill you in, but I'll need to know a bunch more about your set up. Wiring things wrong could do a lot of damage. When you say you have a swap, do you mean an S30 with a turbo motor? When you say you have a starter relay, do you mean you use a relay to trip the starter solenoid you aren't passing a large amount of current through the ignition switch? When you refer to installing a diode, exactly where do you mean and for what purpose? Flyback diode on the relay coils? Backfeed diodes on transistor driven circuits? To wire up an anti-grind circuit you install a relay between the ignition switch and (in your case, presuming what I know about your set up) your starter relay. You wire it so when the relay is energized the key cannot engage the starter. It is the same as wiring a starter kill for an alarm system. The difference is rather than having the relay engaged when the alarm is armed, you have it engage when the turbo timer is active. How this is wired will vary with what turbo timer you have. It can be wired with the ignition out wire from some turbo timers, or ideally from a spare 'active' output from the turbo timer. Exactly what turbo timer do you have and how is it wired in to your car? Do you have an ignition relay that handles most of the current required to run the car or does the ignition switch handle large amount of current? I should be able to give you fairly detailed help with that information. Quote Link to comment Share on other sites More sharing options...
rayaapp2 Posted November 2, 2009 Author Share Posted November 2, 2009 Flyback diode on the relay coils to protect the ECU circuit. Personally I have a RB25DET swap. The starter solenoid signal wire was a 10 gauge wire. I dont have an amp probe that will handle more than 10 amps without frying. So I was stuck with assuming that the large wire that wasnt very long was designed to handle a large current. That is why I installed the relay, but I should have installed a flyback diode to prevent that relay coil from killing the circuit in the ECU. And the same thing with the fuel pump circuit. I installed the APEXi Pen sized turbo timer 405-A011 using the circuit above. Its installed correctly. I'd triple checked it before realizing that the wiring was not an issue, but really it was the original design on the starter circuit inside the ignition switch. At first glance this timer doesnt have an output that can be used to trigger the new relay. I may have to open the "relay" box up that was included with the turbo timer to find what we are looking for. Most of my high amp circuits are running from relays now. The Ignition wire runs relays for the fuel pump and the ecu. this is the APEXi wiring diagram Quote Link to comment Share on other sites More sharing options...
eec564 Posted November 2, 2009 Share Posted November 2, 2009 For some reason I couldn't see those pictures on my computer at home. I'm at work now (I'm actually working, shhh, don't tell anyone) and I see what you mean. The very first picture you posted shows the correct wiring for a turbo timer or remote start system with anti-grind. The starter wire is cut and run through the harness so that when the system is active (or the alarm is active, that's what the orange wire input is for, orange is the universal color for alarms 200ma negative output when armed) the starter is disabled. If you're using the vehicle-specific harness from Apexi does it route the starter wire in to the relay box and then to the harness? The battery, ignition and accessory can be a simple tap. -Eric Quote Link to comment Share on other sites More sharing options...
rayaapp2 Posted November 3, 2009 Author Share Posted November 3, 2009 If you're using the vehicle-specific harness from Apexi does it route the starter wire in to the relay box and then to the harness? The battery, ignition and accessory can be a simple tap. -Eric Actually I am not using the APEXi specific wire harness. I made a phone call to their tech line to find out what those 3 wires were for and how to hook them up. They do not make a specific harness for my 1974 Datsun...lol I cannot find a source on the turbo timer to run a simple relay cut switch from. That has been the problem since I started. I feel better now though that someone is on the same page as me though. Quote Link to comment Share on other sites More sharing options...
eec564 Posted November 4, 2009 Share Posted November 4, 2009 Alright. Can you tell me what those three wires do, and how you connected them? Did that include power to the unit and ground? Do you have an alarm system, specifically, so you have an alarm system with a starter kill? Presuming a mostly stock Z harness, here's what I'd do. This is assuming you simply have the stock Z ignition switch wired to an ecu relay that powers the ecu and fuel pump, etc, and to a starter relay. Following the attached schematic, wiring in a relay as a starter kill that will be triggered whenever the turbo timer is active. This way when the turbo timer outputs + on its ignition output wire it will supply power to the relay cutting off the key's ability to trip the starter motor and power the vehicle's ignition to keep the car running. The diode will make sure power will not feed from the ignition (as powered by the key) and cut off the starter motor. There IS a catch here, that MUST be noted to prevent fire. The diode must have a current rating sufficient to run the ignition. You can test the current draw of the ignition with a good multi-meter in amp mode. Remove the plug from the back of the ignition switch and hook an amp meter (multi-meter set to the 10-amp scale) to the battery + and ignition wires. This will turn on the car, then hot wire the starter to get things running. Note the current, 0.2 amps or so indicates the ignition is driving one relay and nearly any diode will do. If the current draw is larger, you must use a diode rated to handle it. If the draw is over a few amps, you should consider using a second relay. In that case a diode would not be needed as the ignition out wire from the turbo timer would be used to trip both relays, one to disconnect the starter from the ignition switch and one to connect battery + to the ignition wire. -Eric Quote Link to comment Share on other sites More sharing options...
rayaapp2 Posted November 4, 2009 Author Share Posted November 4, 2009 That probably wont work. The ignition wire for the timer is hooked directly to the ignition wire on the car. It appears it uses this wire as a sensor circuit. I think the timer senses the power being turned off and then powers up the circuit. So putting a diode between the timer and the ignition would not work with this particular unit. There isnt any other way that I can fathom that this unit works. Quote Link to comment Share on other sites More sharing options...
eec564 Posted November 4, 2009 Share Posted November 4, 2009 The unit HAS to get power from battery + somewhere, it can't simply power itself from the vehicle ignition wire. At the very least the unit would need ground, battery +, and ignition out. How many wires are there coming from the unit (used or unused) and what do they do? Quote Link to comment Share on other sites More sharing options...
rayaapp2 Posted November 5, 2009 Author Share Posted November 5, 2009 I forgot you cant always see the picture there are 6 wires. The unit pulls power from 12V constant source. I used the big white/red wire at the ignition switch. the wires coming off the unit are: source 12V RED ignition BLUE accessory GRN O2 WHITE e brake light GREY ground BLK So it senses ignition off and pulls power from the constant back to the ignition through the built in relay device. Quote Link to comment Share on other sites More sharing options...
eec564 Posted November 5, 2009 Share Posted November 5, 2009 I'm presuming that it's an automatic timed turbo timer, from how you're describing it. I'm used to the ones where you push a button to engage them and the unit engages power to the ignition circuit and starts a countdown. I don't see how it could sense via the ignition (blue) wire. Waiting for the ignition power to go off then rapidly switching it back on seems like it could cause lots of issues. It would have to detect ignition on, and at that point start holding the ignition on, then detect key off with the accessory wire and start the countdown. Or it detects via the e-brake wire to know when to kick-on, then senses via something else. Do you have the acc wire tapped in to the car? Try unhooking (if you used nice and easy quick-disconnects) the accessory wire just for fun and seeing if the timer works properly. If it does, you can use that wire to power the relay to cut off the starter without a diode or tapping anything else. The other option would be to build a universal anti-grind circuit. It monitors some function of the engine, such as tach or o2 sensor, and cuts off the starter ANY time the engine is running, completely independently of the turbo timer. -Eric Quote Link to comment Share on other sites More sharing options...
lowrider Posted April 8, 2011 Share Posted April 8, 2011 (edited) I'm presuming that it's an automatic timed turbo timer, from how you're describing it. I'm used to the ones where you push a button to engage them and the unit engages power to the ignition circuit and starts a countdown. I don't see how it could sense via the ignition (blue) wire. Waiting for the ignition power to go off then rapidly switching it back on seems like it could cause lots of issues. It would have to detect ignition on, and at that point start holding the ignition on, then detect key off with the accessory wire and start the countdown. Or it detects via the e-brake wire to know when to kick-on, then senses via something else. Do you have the acc wire tapped in to the car? Try unhooking (if you used nice and easy quick-disconnects) the accessory wire just for fun and seeing if the timer works properly. If it does, you can use that wire to power the relay to cut off the starter without a diode or tapping anything else. The other option would be to build a universal anti-grind circuit. It monitors some function of the engine, such as tach or o2 sensor, and cuts off the starter ANY time the engine is running, completely independently of the turbo timer. -Eric I realize that this thread is old, but I feel as if I can finally put this to bed since no one posted the final solution. A little background, I bought an Apexi turbo timer off of eBay. I made my own adapter harness that plugged into the Ignition switch and the factory ignition plug. The adapter harness then had a plug for the turbo timer harness spliced into it. I originally installed the Turbo timer like so: turbo timer-------------ign harness red wire ------------- 12v constant green wire ------------- 12v ign on blue wire ------------- 12v acc I came across the problem of the starter engaging when turning the ign switch to the lock position. I did some searching and found this thread. I took some of the ideas in the thread and applied them to fix the problem. To solve the grinding issue I removed the acc power wire and used it to power a relay that cut the connection to the starter while the turbo timer was running. No more grinding! Forgive the paint drawing, but this is how the revised wiring ended up. A picture of the adapter harness with the relay installed. Again, I thought I would assist and put the final touch on the thread. Edited April 8, 2011 by lowrider Quote Link to comment Share on other sites More sharing options...
rayaapp2 Posted April 19, 2011 Author Share Posted April 19, 2011 Well thats Brilliant! And I already have the starter on a a relay... Thank YOU! Quote Link to comment Share on other sites More sharing options...
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