Ok so this just started, you get in and turn the key nothing happens, no radio nothing like the battery is dead, but you run a hot wire from battery to coil and jump through the starter relay and it fires right up and all power is back, unhook the oil jump wire and drive away...get somewhere else and turn key off... Loses all power again..my only thought was maybe key switch but it has to be in for car to run and when you turn key off it Shuts off like normal, I'm horrible at explaining things and I hope someone knows what I am talking about or at least has ideas haha any help is appreciated.
Help, No power when turn key
- Thread starter aarong5
- Start date
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67Dart273
Well-Known Member
Start with this MAD article. Whether you bypass the ammeter or not, it points up the "thing" with these systems:
http://www.madelectrical.com/electricaltech/amp-gauges.shtml
The diagram on that page, reposted below, shows the simplified main power path
Your most likely suspects are probably poor connections at the fuse link, bulkhead connector, ammeter and associated wiring, and possibly the ignition switch. In rare cases, but it does happen, the welded splice fails. This is a factory splice in the black ammeter wire under the dash. If it gets down to checking that, you must pull the cluster, untape the under-dash harness starting at the black ammeter wire and follow it down a few inches.
http://www.madelectrical.com/electricaltech/amp-gauges.shtml
The diagram on that page, reposted below, shows the simplified main power path
Your most likely suspects are probably poor connections at the fuse link, bulkhead connector, ammeter and associated wiring, and possibly the ignition switch. In rare cases, but it does happen, the welded splice fails. This is a factory splice in the black ammeter wire under the dash. If it gets down to checking that, you must pull the cluster, untape the under-dash harness starting at the black ammeter wire and follow it down a few inches.
BillGrissom
Well-Known Member
Sounds like your ignition switch is bad, with both the ACC and START (IGN2) positions failed. However, it could be in the wiring, though the ACC circuit doesn't go thru the bulkhead like the IGN2 wire does. You didn't state which car, if the 67 you are in luck since the ignition switch is easy to change and only costs ~$12 as I recall.
Inertia
Well-Known Member
Have you cleaned the batt terminals,, particularly the pos one ?
Yeah it's the67, but if the key switch was bad would it keep running after I jumped it through the starter relay, and have all the guages work and power to the fuse box? Seems like it shouldn't work at all if the switch is bad but idk... This cars always got problems but I guess that's how a 40+ year old car is haha
At the firewall there is a fusible link with a service/safety disconnect. All of the power inside the cabin goes through that. If that connection fails completely you'll not even have a dome lamp on.
It is shown in the drawing above. Rewiring all the way to the ALT' gauge may or may not be needed. That disconnect is exposed to the elements so it does corrode. Might be the only problem.
It is shown in the drawing above. Rewiring all the way to the ALT' gauge may or may not be needed. That disconnect is exposed to the elements so it does corrode. Might be the only problem.
67Dart273
Well-Known Member
'T's the reason I posted the link and diagram. You may have an intermittent bad connection, that is, a connection that "comes and goes." Placing a LOAD on the circuit may make the bad connection break. On the other hand, if it "decides" to run, the charging system may produce enough (sometimes!!!!) to "arc" over the bad connection.
You need to learn some troubleshooting, how to check, don't guess.
Start by the basics. Pull and wiggle wires, look for loose connections. Remove and clean the battery cable clamps. Wiggle the wire at the starter and starter relay, wiggle the bulkhead connector, and pull it loose and inspect it.
READ the MAD article. Even if you don't bypass the ammeter, that article shows you the pitfalls of the main power distribution in these cars.
BillGrissom
Well-Known Member
Yes. Several independent contacts are made in the ignition switch. The "run" contacts could be good, but not the "start" contacts, and the "ACC" contacts could be erratic. The "run" circuit (IGN1) does not make a connection when the key is in the "start" position, even in a perfectly good switch. "run" only gets power when you let go of the spring-loaded "start" position. Still, it is rarer for the ignition switch to go bad than the bulkhead and wiring connections, especially since you have been having other electrical problems, and you live in the east where most of your copper terminals are probably green (copper oxide doesn't conduct).
Beatnik
Well-Known Member
Put a test light on the yellow wire coming off the starter relay. Have someone turn the key to crank. If it lights up the switch is good. Just an easy thing to eliminate. Good luck.....my money is on the switch or bulkhead wiring based on what your describing. Check NSS wiring too. Easy to eliminate by bypassing the NSS switch and see what happens. Also turn the key to crank and go from P to N back/forth....never know but I don't think thats the issue based on the symptoms but again it's an easy thing to eliminate. Let us know at you find!
I've already bypassed the nutral safety switch long ago, but the accessory setting on the switch would sill work when the NSS went bad I'm gonna try some of these out tomorrow and see if I can't trace it down
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