Turn key, battery goes flat, ignition switch smoky. |
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Turn key, battery goes flat, ignition switch smoky. |
jaredmcginness |
Nov 30 2020, 08:25 PM
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#1
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... Group: Members Posts: 502 Joined: 12-June 19 From: Baltimore Member No.: 23,209 Region Association: MidAtlantic Region |
Me again.
It’s gonna be one problem post a day, until next years Octeener fest. (IMG:style_emoticons/default/idea.gif) So close here to firing this motor (in the car)(works fine outside of it) I’m thinking I have a short somewhere in the ignition, but everything seems to check out. Notes: Early car, early VW style switch. (After market) Turn key, ACC works fine, fuel pump relay clicks, all electrics work. 12v to coil, 12v to starter, power supply relay is good. Turn key to run, Nothing - power goes flat, as long as I hold the key down. Messing around a bit, tried again and the ignition switch/column starts smoking and the IGNS wires are warm. I believe once she smokes she’s done. I’ll buy a new switch tomorrow, but I’m trying to probe if this sounds like more than a switch. All my wiring matches the bowlsby pages. Battery is new. Switch was new (but probably Taiwan crap), new ground to battery and new ground strap. Cleaned every ground I can find. Does not even considering the idea of cranking. Starter cranks fine when manually jumped. Now that my smoke is out, queue the ‘Replacement Can’ comments. (IMG:style_emoticons/default/bye1.gif) |
jaredmcginness |
Nov 30 2020, 08:49 PM
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#2
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... Group: Members Posts: 502 Joined: 12-June 19 From: Baltimore Member No.: 23,209 Region Association: MidAtlantic Region |
Ahh yes, found it. I’ll need to add this to my order.
(IMG:http://www.914world.com/bbs2/uploads/post-22428-1558925713.jpg) |
Spoke |
Nov 30 2020, 09:07 PM
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#3
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Jerry Group: Members Posts: 6,972 Joined: 29-October 04 From: Allentown, PA Member No.: 3,031 Region Association: None |
Early car, early VW style switch. (After market) Turn key, ACC works fine, fuel pump relay clicks, all electrics work. 12v to coil, 12v to starter, power supply relay is good. I believe there are only 3 positions for the ignition switch: Off; Running; and Start. So when you "Turn key", this is to the Running position, correct? The 12V to the starter is measured on the large wire from the battery, correct? 12V on the large wire is constant regardless of the key position. The smaller yellow wire comes from the ignition key when in the "Start" position and puts 12V on the yellow wire to the bendix on the starter. QUOTE Turn key to run, Nothing - power goes flat, as long as I hold the key down. Messing around a bit, tried again and the ignition switch/column starts smoking and the IGNS wires are warm. You mean when you go to the "Start" position, correct? In the Start position the yellow wire on the starter should be powered. This wire goes from the ignition switch to the relay board then to the starter. Try disconnecting the harness on the relay board from the cabin and see if the power goes flat. |
jaredmcginness |
Nov 30 2020, 09:47 PM
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#4
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... Group: Members Posts: 502 Joined: 12-June 19 From: Baltimore Member No.: 23,209 Region Association: MidAtlantic Region |
Correct. When I turn key to Run, I have power. When I turn from Run to Start, it goes flat.
I will remove the cabin harness from relay (the 14 pin one, right?) |
Mikey914 |
Nov 30 2020, 11:39 PM
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#5
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The rubber man Group: Members Posts: 12,638 Joined: 27-December 04 From: Hillsboro, OR Member No.: 3,348 Region Association: None |
Check the switch itself. There were some crappy ones made that would allow the switch to ground out and melt it.
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mepstein |
Nov 30 2020, 11:46 PM
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#6
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914-6 GT in waiting Group: Members Posts: 19,237 Joined: 19-September 09 From: Landenberg, PA/Wilmington, DE Member No.: 10,825 Region Association: MidAtlantic Region |
Do you still have the switch I gave you. Does it work?
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jaredmcginness |
Dec 1 2020, 05:15 AM
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#7
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... Group: Members Posts: 502 Joined: 12-June 19 From: Baltimore Member No.: 23,209 Region Association: MidAtlantic Region |
Sound about right then Mikey, I think this was one of the $35 crap switches with thinner gauge wires. Hope this is the issue. Do you still have the switch I gave you. Does it work? I have the tumbler and key installed, I don’t recall there being a switch. But the tumbler works excellent. |
Superhawk996 |
Dec 1 2020, 06:42 AM
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#8
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914 Guru Group: Members Posts: 5,746 Joined: 25-August 18 From: Woods of N. Idaho Member No.: 22,428 Region Association: Galt's Gulch |
I’m thinking I have a short somewhere in the ignition, but everything seems to check out. Me too. You posted a lot of other good info on what parts you have but the only thing that really matter is wheter or not the Digital Multimeter says things check out. DMM and wiring diagram are your friend. All else is speculation. Let me find the link to half split troubleshooting method I've previously posted. Post #6 http://www.914world.com/bbs2/index.php?showtopic=340700 |
jaredmcginness |
Dec 1 2020, 07:48 AM
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#9
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... Group: Members Posts: 502 Joined: 12-June 19 From: Baltimore Member No.: 23,209 Region Association: MidAtlantic Region |
the only thing that really matter is wheter or not the Digital Multimeter says things check out. DMM and wiring diagram are your friend. All else is speculation. I've never heard of the half split method. I just read a few articles and will apply this tonight. I Prime same-day ordered a better DMM with continuity. Probably much over due from the POS $7 Harbor freight one I've had for years. Always appreciate your advice. |
VaccaRabite |
Dec 1 2020, 08:56 AM
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#10
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En Garde! Group: Admin Posts: 13,423 Joined: 15-December 03 From: Dallastown, PA Member No.: 1,435 Region Association: MidAtlantic Region |
Do you have a solenoid at the starter to handle the big load for starting the car? If not, do that.
As stock, all the power for starting the car goes all the way from the battery to the ignition switch and the back to the starter. The solenoid lets you run a thick cable from the battery to the starter motor and keeps the switch at low amperage. Most of us use a Ford solenoid, the wiring is very simple and they are CHEAP. I have mine bolted to the back of the engine tins so it sits right next to the starter. This won't fix you immediate problem, but will keep your starter switch from melting in the future. Zach |
Superhawk996 |
Dec 1 2020, 09:19 AM
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#11
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914 Guru Group: Members Posts: 5,746 Joined: 25-August 18 From: Woods of N. Idaho Member No.: 22,428 Region Association: Galt's Gulch |
As stock, all the power for starting the car goes all the way from the battery to the ignition switch and the back to the starter. Zach Be careful with this - I'll modify: As stock, all the power for starting the car goes all the way from the battery to the ignition switch and the back to the OEM Starter SOLENOID. The starter motor current (upwards of 100 amps or more) is not drawn through the yellow wire via the ignition switch. The yellow wire handles the OEM starter solenoid current not the actual starter motor current. |
jd74914 |
Dec 1 2020, 09:46 AM
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#12
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Its alive Group: Members Posts: 4,776 Joined: 16-February 04 From: CT Member No.: 1,659 Region Association: North East States |
Check the switch itself. There were some crappy ones made that would allow the switch to ground out and melt it. (IMG:style_emoticons/default/agree.gif) I had this happen with 2 replacement switches before putting in a NOS. (IMG:style_emoticons/default/headbang.gif) Once while driving with the top on and windows up-couldn't believe how fast plastic smoke filled the cabin. |
fixer34 |
Dec 1 2020, 04:24 PM
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#13
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Senior Member Group: Members Posts: 1,073 Joined: 16-September 14 From: Chicago area Member No.: 17,908 Region Association: Upper MidWest |
Ahh yes, found it. I’ll need to add this to my order. (IMG:http://www.914world.com/bbs2/uploads/post-22428-1558925713.jpg) This won't work anyway. The smoke will go backwards since it is positive earth (ground). |
mepstein |
Dec 1 2020, 05:06 PM
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#14
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914-6 GT in waiting Group: Members Posts: 19,237 Joined: 19-September 09 From: Landenberg, PA/Wilmington, DE Member No.: 10,825 Region Association: MidAtlantic Region |
Ahh yes, found it. I’ll need to add this to my order. (IMG:http://www.914world.com/bbs2/uploads/post-22428-1558925713.jpg) This won't work anyway. The smoke will go backwards since it is positive earth (ground). Bob Russo has a big sign on the Mirage race car for positive ground. Attached image(s) |
jaredmcginness |
Dec 1 2020, 06:32 PM
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#15
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... Group: Members Posts: 502 Joined: 12-June 19 From: Baltimore Member No.: 23,209 Region Association: MidAtlantic Region |
OK.
Guys, as usual I step back into my question threads, solved, with my head hanging low. I tested continuity on the relay board. 100% all around. Cleaned up the ground bundle really well... Nice to know. But still leaves me hanging. The new ignition switch arrives. (lucky to have found one in town (BaltAuto - $59) I start stripping down the column.... Low and behold..... (IMG:http://www.914world.com/bbs2/uploads_offsite/i.imgur.com-23209-1606869157.1.jpg) You cannot make this crap up. I installed that switch over a year ago, actually one of the first things I did when I bought the car (P.O. Drilled the ignition out) Used a cheapo ebay switch - did not check my work. You can imagine my laugh - and face when I saw this. It could not be MORE grounded to the body, you can actually see through it. Feel free to flame me. What I have learned: -The half split method. -Every ground I can find is now clean. -Relay board is in good shape. -I've tested every relay I own. -I strongly dislike early switches. For the guys reading this down the road. Dont buy thee cheapo $22 switch. (IMG:http://www.914world.com/bbs2/uploads_offsite/i.imgur.com-23209-1606869157.2.jpg) Here are the differences: Ebay (jbugs)($22) vsU.S. Standard #403 Ign. Switch ($59) Ebay is junk clamped, wires are loosely attached, each wire has broken strands. Fits loose in the column. US Standard #403 Soldered connection, Nice and tight fit in the column. The actual switch mechanism is tighter. Also... Made in Germany? (IMG:http://www.914world.com/bbs2/uploads_offsite/i.imgur.com-23209-1606869157.3.jpg) I will hang the old switch above my work bench, to remind me to think and check the easiest thing first. The root of the problem. Thank you for the help and responses. The car cranked, first try. |
FlacaProductions |
Dec 1 2020, 07:00 PM
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#16
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Senior Member Group: Members Posts: 1,554 Joined: 24-November 17 From: LA Member No.: 21,628 Region Association: Southern California |
I always appreciate a graceful recovery. Nice work - glad it ended well!
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Superhawk996 |
Dec 1 2020, 07:08 PM
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#17
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914 Guru Group: Members Posts: 5,746 Joined: 25-August 18 From: Woods of N. Idaho Member No.: 22,428 Region Association: Galt's Gulch |
Good job finding that pinched wire! No shame there.
Would have been a shame to start guessing at fixes, modifying wiring, adding solenoids, etc., just hoping for a fix. We all learn by our mistakes. Been there done that! I'm going to suggest that you do one more homework reading assignment on half split method. Here's the punch line to encourage you to read it. "Lesson learned: do not take short cuts, do not assume the part you can easily test is the part that is broken, and do not assume you have found the problem the first time you find something that does not look right. " So unless you've fully verified your new switch and repaired wire circuit to have low resistance continuity with a DMM all the way back to the starter solenid - You're not done. https://rule11.tech/troubleshooting-half-split/ |
Tom |
Dec 3 2020, 01:43 PM
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#18
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Advanced Member Group: Members Posts: 2,139 Joined: 21-August 05 From: Port Orchard, WA 98367 Member No.: 4,626 Region Association: None |
Superhawk996,
In the military we learned the divide and conquer method. Essentially the same as what you learned as the half split method. And if one does not understand what the complete circuit is composed of, and how it is supposed to work, you are starting in a hole and digging the hole deeper. I have seen it too many times where someone working on an electrical/electronic circuit and does not understand the circuit and ends up making the problem worse. A good set of wiring diagrams and or schematics is a must. The Haynes manual wiring diagrams have lead many to make the problem worse. Too small and too easy to jump a trace by one wire, ending up with measurements that make no sense. One more tip: when using a multimeter, always test the meter on a known good power source of the same value you are checking for both before and after your readings have been taken. Just imagine taking reading for an hour or two and not getting anything that makes sense and then trying the meter on your known good 12V battery and the reading is 3 volts. Just wasted a couple of hours. Tom |
Costa05 |
Dec 3 2020, 03:40 PM
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#19
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Member Group: Members Posts: 320 Joined: 27-October 16 From: Phoenix, Arizona Member No.: 20,535 Region Association: Southwest Region |
Here is my switch I just replaced last week. Notice the crack in it. Had similar problem as you but no short/smoke. Also putting in new solenoid in engine bay to lighten the load going to my new ign switch as others did.
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