Dudeboy Posted June 26, 2014 Share Posted June 26, 2014 (edited) I am stumped on this! I have a Longacre switch panel toggle switch/pushbutton start and Longacre Heavy duty wiring harness with these instructions: Brown wire – to battery or power source (you can pick up power at the starter motor). The larger ring terminal goes to the battery cable terminal. Two Yellow wires – one wire to ignition system; one wire to any accessory you want to shut off with the ignition – gauge and warning lights, tach, etc. (NOTE: Both yellow wires are connected to the same source. Two separate wires are provided for your convenience.) Green wire – to your starter solenoid. The smaller ring terminal goes to the solenoid. From the Speartech harness and instructions the LS1 orange wire is connected to the battery. We connected the LS1 pink wire to one of the Longacre yellow wires for ignition crank and run. We flipped the toggle switch that is the other yellow wire on Longacre panel connected to fuse panel and the LS1 diagnostic port lights up and fuel pump kicks in. I hit the pushbutton and it fires right up! Problem!! The toggled switch does not turn car off. I have to disconnect the battery to turn off engine. If you have toggle switches/ pushbutton starting what I am doing wrong? Let me add the car has been re-wired with a Kwik Wire 8 Circuit hot rod harness. By the way get this straightened out, bleed the brakes and bodywork/paint finally done !! Edited June 26, 2014 by Dudeboy Quote Link to comment Share on other sites More sharing options...
Domzs Posted June 26, 2014 Share Posted June 26, 2014 Will it start w/o turning on the toggle switches ? Quote Link to comment Share on other sites More sharing options...
Dudeboy Posted June 26, 2014 Author Share Posted June 26, 2014 Dom, No, it want start without flipping the toggle (behind red cover). I flipped that switch on I hear fuel pump, gauges and diagnostic lights come on. It started up and scared the sh$$ out of me ! Hit the toggle to turn it off and it kept running so we kind of went into panic mode to turn it off. I have the Kwik wire manual in front of me and I am going over the ignition and motor group wiring again, and trying to figure it out. Quote Link to comment Share on other sites More sharing options...
Domzs Posted June 26, 2014 Share Posted June 26, 2014 How did you wire up your radiator fan(s) ? ECM control or toggle switch control ? Quote Link to comment Share on other sites More sharing options...
Dudeboy Posted June 27, 2014 Author Share Posted June 27, 2014 (edited) The fans are controlled by ECM. The two toggle switches to the right are driving lights and wipers (do not plan on driving in rain!! ) but just in case. Wired the car a while back, but I am going to tear into the wiring Saturday. By the way Thanks - trying to think logically about car electrics. Edited June 27, 2014 by Dudeboy Quote Link to comment Share on other sites More sharing options...
mattd428 Posted June 27, 2014 Share Posted June 27, 2014 Pink wire should go to you toggle switch. That should be on start crank run wire Quote Link to comment Share on other sites More sharing options...
Domzs Posted June 27, 2014 Share Posted June 27, 2014 Reason for asking , because i have seen people by-passed the fan control by using ignition power to activate the fan ( fan runs when key is on ) . By doing that , the engine won't shut off with key off . Fan motor becomes an alternator when key is in off position , feeds enough power to keep the engine running . Quote Link to comment Share on other sites More sharing options...
Dudeboy Posted June 27, 2014 Author Share Posted June 27, 2014 I think my problem may be the Longacre heavy duty harness. The two yellow wires branch off, one tied into accessories, the other yellow wire connected to pink wire for ECM. But, there is a green wire in the harness that is connected to the starter solenoid. This may be problem. Quote Link to comment Share on other sites More sharing options...
Domzs Posted June 27, 2014 Share Posted June 27, 2014 Use a test light or a voltmeter ( prefer ) to test the yellow wires for voltage , should be no voltage when off . Quote Link to comment Share on other sites More sharing options...
rsicard Posted June 27, 2014 Share Posted June 27, 2014 The red guarded toggle switch is for ignition on and off. The brown wire must go from the heavy post on the starter up to the ignition switch and also jumpers to the push button start switch. The other side of the ignition switch likely goes to the pink wire on the LSx harness. The other side of the push button switch goes to the solenoid on the starter. The yellow wires connect to the opposite side of the ignition toggle switch where the pink wire is connected to. When the ignition switch is thrown to the on position, it supplies power to the LSx PCM and also to the other two switches on the panel. There needs to be an inline fuse, near the starter, (40 amp) on the smaller wire, going back to the switch panel, connected to the large starter post. The fuse protects the small wire coming from the starter going to the switch panel and also the accessories. There is one hell of a lot of energy at the heavy post on the starter. Should the small wire short to frame or body, the small wire without a fuse could cause a FIRE. Quote Link to comment Share on other sites More sharing options...
rags Posted June 27, 2014 Share Posted June 27, 2014 How do you have the alt tied into the car? Do you have the BAT terminal going directly to the battery of do you have it tied into the wiring harness after the starter? Something is backfeeding the fuse panel after the alt is supplying current. To test my theory, pull all of the fuses at once on the fuse panel and see if the toggle switch then works. Quote Link to comment Share on other sites More sharing options...
rsicard Posted June 27, 2014 Share Posted June 27, 2014 On the subject of the Alternator, two fuse are needed for it. One is a 20 amp for the field excitation from the ignition switch post along with the LSx PCM pink wire. The other needs to be 100 amp inline with the alternator heavy post output to the battery or battery connection at the starter your choice. Have a LOT of experience in wiring Aircraft and Cars. Quote Link to comment Share on other sites More sharing options...
rags Posted June 27, 2014 Share Posted June 27, 2014 Actually the field excitation is done through the ECU wiring harness. The direction of current on that wire is into the alternator. I agree with needing to fuse the pink wire as well as the alternator output. Any insight on troubleshooting the OP's problem? Do you agree that the second yellow wire going to the fuse panel is backfeeding the yellow wire going to the ECU's pink wire? Quote Link to comment Share on other sites More sharing options...
Dudeboy Posted June 27, 2014 Author Share Posted June 27, 2014 Gentlemen I am reading what you have posted and looking at manuals and the connections on the car. I have a CS130/144 Alternator with a battery lug and also a pigtail connection. On the connection end of the pigtail there are two male spade connectors. The instructions were to connect the alternator exciter based on two options. 1. 12 volt ignition fused when not using indicator lamp 2. 12 volts ignition fused when using indicator lamp. I use #2 ? When we were doing the wiring I did not have the Autometer volt guage, the stock volt guage was still in dash? Rags, the the exciter wire originates from my fuse panel harness and I agree there is back feed. From the LS1 pcm harness (Speartech) I only had to make connections for gray wire(fuel pump) orange wire(battery), and pink wire (ignition). I am going to test your theory. Rsicard, fuse panel and switch is fused just as you pointed out and the wiring is heavy guage. Could it be as simple removing the connection from #2 to #1 ? Keep them ideas coming, jumping on it first thing in the morning. Quote Link to comment Share on other sites More sharing options...
rsicard Posted June 28, 2014 Share Posted June 28, 2014 Dudeboy, if using Option 2, the "F" terminal on the alternator should be at 12-14 volts when the alternator is operational. When the alternator is not charging, terminal "F" should be near the same electrical potential as the negative side of the battery. With the charge light in the circuit, it will be lit as one side should have 12-14 volts (supplied through a small amperage fuse) and terminal "F" will essentially be at battery negative. When the alternator is CHARGING, the charge light will have 12-14 volts on both sides of the lamp having the same electrical potential on both sides of the lamp there will be no current flow through the lamp and thus will NOT be LIT. Quote Link to comment Share on other sites More sharing options...
Dudeboy Posted June 29, 2014 Author Share Posted June 29, 2014 (edited) Life got in the way today, no car time. But, was calling all the hot rod and electric gurus I know and apparently my car not shutting off is a combination of a new chassis harness and my CS 130 alternator. I was to add a diode or "idiot light " on the alternator exciter wire #914 for painless and for my harness it is wire #14. I did a search on back feeding alternators and this is a common problem when you upgrade the harness and upgrade to a cs130 alternators. Try get in garage and test it out the theories. Edited June 29, 2014 by Dudeboy Quote Link to comment Share on other sites More sharing options...
socorob Posted June 29, 2014 Share Posted June 29, 2014 The alternator light would have to be a light bulb so it can see a load If not you would have to put a resistor there so the exciter wire can see a load. i can't remember the value but I think 270? Quote Link to comment Share on other sites More sharing options...
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