Car won't start - bad ignition switch?

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FrozenCaveman

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I jumped in my 71 /6 Scamp this morning to get to work and was greeted with what I thought was a dead battery. Turned the ignition and all I got was the oil pressure idiot light, no cranking at all. Weird. I cleaned the terminals and boosted the battery - same result.

What are the common symptoms of a bad ignition switch? I've noticed that I can occasionally take the key out of the ignition and the door buzzer will come on when I open the door. I jiggle the switch and the buzzer stops. It happens maybe 5% of time.

Assuming the battery voltage and connections all check out when I go over it this weekend, what's my next troubleshooting step? I drove it home last night, no problems. It's my everyday car, so I'd like to get it going ASAP.

Thanks, guys.

-John
 
Neutral safety switch and starter relay need to be checked.
 
just something to try. with your car in park and the key in the run position and preferably someone inside with there foot on the brake jump the wire coming from your battery to the starter relay to the wire going to the starter from the same relay.

if it starts great there is a problem somewhere in the components connected to that relay (neutral safety switch, ignition switch, or the relay its self)

to check the NSS. ground the lower right vertical terminal on the starter relay the wire conected to it is brown, i believe, and has a funky can only plug in to this terminal plug

turn the key if it starts the problem is in the NSS or its wiring.

to check the ignition switch. check the voltage between ground an the lower left yellow wire on the starter relay (The Ham below reminded me) when the key is in the starter cranking position. i had 11.67 volts at the switch and it seems to be fine for now if its vary low the problem is some where in the switch or its wiring.

if it is neither of these things it might be the relay its self or something totally unrelated that i dont know about yet. Id replace it anyway.
 
1. Use a test light or voltmenter to see if you are getting approx battery voltage to the yellow lead on to the starter relay when you turn the key to START (crank); that is the +12v sent from the ignition switch to activate the starter relay. If not, then look at the ignition switch and the yellow wiring between the starter relay and the ignition switch and through the firewall connector.
2. If above checks good, then short the starter relay terminal (the one with the wire with the brown wire with yellow trace) to ground. If it starts with that, then the transmission neutral safety switch is bad or the brown-yellow trace wire is broken.
3. If it still does not start with the above, then bypass the starter relay. Jumper from the large stud on the starter relay to the small stud on the starter to momentarily activate the starter, be in Park and stay away from th fan. This will pull a bit of current so use a large jumper lead. If this works, replace the starter relay. If not, repalce the starter.

(BTW, I am going off of a '70 Dart schematic......)
 
Connections, connections, connections!! Clean them ALL!! Most of the time it is a connection that fails! If the dome light goes out when you turn the key to start, it is certainly a connection!! Geof
 
Sorry, had some problems with my internet connection this morning... Thanks for all the replies!

I went to just do a quick check on the dome light while cranking before getting on the wiring and it started right up!! What the crap.... So now I'm more bothered than before. Last night I tried it in neutral, in drive, in park, wouldn't make a sound. The only difference today is that the car is sitting in the sun and it's probably warmer. So maybe a connection somewhere??? With everything working, I'm not sure I can troubleshoot it... :/
 
The yellow wire at the start relay should get 12 volts evey time the ign' switch goes to the start position. If it does the switch is good. If the relay doesn't click and engage the starter every time. the relay or the neutral safety switch is the problem. Next test is short the relay terminal the brown wire is on to ground. If the relay now clicks every time the switch goes to start without fail the neutral safety switch in the problem.
If the relay doesn't click the relay is the problem.
If you don't mind throwing a few dollars at it, forget diagnosing and replace the relay.
 
Sweet. I've got a NAPA here that can get parts within a couple hrs, so I went ahead and bought a new starter relay. It won't hurt to have it as a spare. Engine cranked over a couple more times, so I might have to wait until the evening or morning to get it to fail if it's ambient temperature related.

Thanks for the help, and if it turns out to be something else after replacing the starter relay and testing the NSS, I'll follow the other procedures you suggested. Thanks!!
 
So now it's really inconsistent. I put my 5 yo in the back to take him to NAPA and it wouldn't start. Took him out, got my test light and jumper wires out, wiggled the starter relay wires a bit after locating it with my Haynes manual (you learn something every day - man, it's nice how conveniently located it is!). And then the car cranked over. Drove it to NAPA and back, no problems. I did notice that my battery hold-down is missing - well, some of it. Looks like it came off at some point - maybe the battery is moving around enough to slightly dislodge the wiring on the relay?

Anyway, I'm going to throw burgers on the grill, grab a beer and wait for it to fail again. LOL. I've got my new relay if I need it.
 
So you don't get stranded, bring some jumper wires from Radio Shack with you (always), the longer thicker ones. You can get 12 V from the big stud on the starter relay. Jump 12 V to the upstream side of your ballast resistor (2 thinner wire, downstream has 2 thicker wires), but don't leave on too long with engine off. That will power your ignition. Bypass the starter relay by jumping 12 V to the thick brown (?) wire going down to the starter (not really thick red one). But insure the car is truly in P and set the parking brake (always).
 
That sounds like a plan, thanks. The clips I have are long enough to route to the ballast resistor - what am I powering? Just want to make sure I'm on the correct side of the resistor for that - I have 3 wires on the side with smaller wires, all blue. I'm not real good with wiring diagrams (I probably wouldn't need to ask these questions!), but it looks like the intent is to send power through the ballast resistor to the ignition module and leave it there while I run the car? Sorry I'm a little unclear about this - then with the other set of clips sending power to the starter, the car will crank and start? Do I then remove the 2nd clips from the starter? How does the ignition key position fit into all this?
 
Hey FC, a step-by-step troubleshooting process was laid out in post #5....with explanations of what this is doing and what to look at. This is not the ballast; the ballast has nothing to do with activating your starter. The problem is in the starter and/or the starter relay circuit, and/or key switch. The starter relay is activated by the key switch, and then the starter relay sends +12V to the starter's solenoid lead (the small wire on the starter) which activates the starter.

You can throw parts at it and sometimes get things fixed, but if it is wiring, you will have to troubleshoot it, step-by-step to know where to look. Being erratic makes it harder.....welcome to the world of machinery!
 
Starter relay is bad or bad connection.....mine is doing the same thing, after the car sits for awhile, it doesn't make a Sound when trying to start it....go under the hood and tap on the starter relay and it pops right off....if I drive the car around town, it will work, but once it sits for more than a few hours, doesn't want to work again. I bought a new relay and it will go in ASAP :glasses7:
 
I have found little spiders find the starter relay to be a nice home. They build a nest between contacts.
 
Frozen,

You are correct on all - remove starter clip after it cranks and fires, leave IGN clip on. When you remove it, the engine will stop. The 3 smaller blue wires sounds like the upstream side of the ballast (normally powered thru the key switch). Your clip is doing what the key switch normally does. On the upstream side, the 12 V feeds in (IGN1) and continues to Vreg and alternator (later cars). I don't know what the 3rd blu wire is. Check your wiring diagram. Maybe a choke heater or such.

Others are correct that I was telling you how to solve more that just your initial problem. If your key switch is erratic, besides not cranking you also may not get ignition power. A few jumper wires can get you home. If your key switch is in the dash, it is easy to remove and cheap. If in the steering column (changed around your year), not easy, but there is a great sticky post w/ photos.
 
Thanks, guys. Bill, I did find the sticky post about changing out the key switch, so if that's needed, I know where to look.

KitCarlson, we have so many spiders out here (it's that time of year) that it wouldn't surprise me if I had something trying to nest in there even though I drive the car regularly.

And nm9stheham, I didn't mean to skip through your post, I just didn't have anyone around this weekend to help me with cranking the motor while I was under the hood. My 5yo wouldn't have been able to help. Hopefully (?) if it fails again, I'm in a position where I have a friend around. As it was, it hasn't failed since Saturday.
 
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