1971 dart Only cranks when I jump the relay.

[jakeborg69]

Hey guys I daily drive a 1971 dart swinger. I’m having a weird issue with my car. Randomly the car didn’t want to crank after I parked it. when I turn the key to the run position the oil light still comes on, and when I twist the key to crank the light dims like it’s sending power out. My first thought was the nss, so I went to the relay and grounded the yellow nss wire terminal thinking I would just bypass it until I can fix it later, but no dice. Next I’m moving on to the relay itself; I don’t think it’s the issue, but it is the easiest thing to fix next in line. Any thoughts. I’m getting tired of jumping the relay every time I need to drive.

 

[67Dart273]

you grounded the yellow? No that should not be correct

Left side "B" s the main battery, the 'big stud.". That is a junction point, and also 1 contact in the relay

Center terminal "S" goes to the starter solenoid, this is the other contact in the relay

Bottom right, S2-18Y is the yellow "start" signal coming to the relay coil from your ignition switch. This is 12V when the key is twisted to "start."

Top right goes to your NSS. This only has one wire, one wire goes to the clutch safety switch with a stick, the brown/ yellow tracer goes to your NSS. THIS ONE IS THE ONE you should ground to test the NSS

So that, plus check that the yellow is delivering 12V in "start." if that happens, and no crank, then it surely is a bad relay

Electrically, you can reverse the wires connect to top right and bottom right. These are each end of the relay coil

 

[Cope]

I had a jumper wire from the hot terminal on my battery for YEARS... ( 71 dart)

Open the hood, touch the wire on the rely and go...

Ha,ha.. never did fix it tho so no help here..
I just ripped all the wire out and built a race car with a licence plate...

No more jumper wire tho!!!

 

[slantsixdan]

It's the _brown_ wire from the relay to the neutral safety switch that you'd need to ground to see if a bad NSS or related fault is causing your problem. The yellow one is relay +feed from the starter contacts of the ignition switch. If removing the brown wire from the relay and grounding that relay terminal lets you crank the engine with the key, it's a bad NSS, a bad brown wire, or (you hope not) a problem with the actuating finger on the rooster comb inside the transmission. if that test doesn't let you crank with the key, there's a problem with the ignition switch or the wiring from the ignition switch to the relay.

 

[jakeborg69]

you grounded the yellow? No that should not be correct

Left side "B" s the main battery, the 'big stud.". That is a junction point, and also 1 contact in the relay

Center terminal "S" goes to the starter solenoid, this is the other contact in the relay

Bottom right, S2-18Y is the yellow "start" signal coming to the relay coil from your ignition switch. This is 12V when the key is twisted to "start."

Top right goes to your NSS. This only has one wire, one wire goes to the clutch safety switch with a stick, the brown/ yellow tracer goes to your NSS. THIS ONE IS THE ONE you should ground to test the NSS

So that, plus check that the yellow is delivering 12V in "start." if that happens, and no crank, then it surely is a bad relay

Electrically, you can reverse the wires connect to top right and bottom right. These are each end of the relay coil

View attachment 1715453318

yep I totally jumped the wrong wire... ha thanks for the info I’ll try it and let you know how it goes I really appreciate the information.

 

[Frank Mopar]

Pull the bulkhead connector apart and check inside.

 

[Darter6]

Also check the connection where the wires from the ignition switch in the column attach to the harness about mid way down the column. I have found burnt terminals at that connection on the 70 up cars causing a no start condition.

 

[Mattax]

yep I totally jumped the wrong wire... ha thanks for the info I’ll try it and let you know how it goes I really appreciate the information.

The heavy 12 gage Brown is power to the starter solenoid.
Connection to the NSS is the one on the other corner terminal.
It may may be brown w/ striped on '71.
That's what the diagram @67Dart273 posted shows

To bypass the NSS, ground the G terminal.

 

[jakeborg69]

Also check the connection where the wires from the ignition switch in the column attach to the harness about mid way down the column. I have found burnt terminals at that connection on the 70 up cars causing a no start condition.

I will definitely check that. Thank you !

 

[jakeborg69]

Hey guys changed the relay and tried grounding the nss terminal. Still no crank. Any other ideas? I’m at a loss besides the starter solenoid

 

[Mattax]

Do you have a multimeter?
Do you have a digital camara?

 

[jakeborg69]

Do you have a multimeter?
Do you have a digital camara?

yes and yes I do.

 

[Mattax]

On the camara, I was thinking some photos may help us. We might see something.
If you're using a laptop you can upload either by dragging and dropping with a mouse or using the upload button and going to the file folder.
Cell phone - I have no idea - but guys do it.

Multimeter.
I'd start with checking for power at the starter wire from the key switch.
Set the meter on DC Votlage.,
Remove the start wire (18 ga yellow) and clip or back probe the positive lead from the meter. Attach the meter neg/ground wire to any convenient ground.
Turn the start key and see if the wire shows battery voltage.

 

[Frank Mopar]

On a separate note, pick up a Power Probe 3. Its the best tool you can have in your tool box for electrical problems.

 

[67Dart273]

Hey guys changed the relay and tried grounding the nss terminal. Still no crank. Any other ideas? I’m at a loss besides the starter solenoid

Time to do some real troubleshooting. "Rig" your meter or test lamp on the yellow wire going to one of the two "push on" flag terminals of the relay. That should have power whenever the key is twisted to start.

Alternatively, pull the yellow wire off the relay. Be sure the car is in park or neutral, Jumper the "big stud" terminal over to that exposed flag terminal. That should activate the relay and crank the engine. If this happens, you are not getting 'start' power from the key out to the relay on the yellow wire.

It might be possible you have more than one problem

Go to MyMopar and download a free wiring diagram and shop manual

 

[Frank Mopar]

Did you pull the bulkhead connector apart and check it? You will see burn marks if the connections are bad.

 

[cudajim]

Did you pull the bulkhead connector apart and check it? You will see burn marks if the connections are bad.

Ok so that's bad advice. He needs to figure out what the relay is not getting first then maybe it's a problem further back toward the ignition switch or maybe it's a problem with the ground side of the relay (neutral safety switch and associated wiring). It could also be a problem with the relay itself, the high current wires to the starter or the starter itself. Follow 67 darts advice and get back to us. It should be a simple fix.

 

[jakeborg69]

Ok so that's bad advice. He needs to figure out what the relay is not getting first then maybe it's a problem further back toward the ignition switch or maybe it's a problem with the ground side of the relay (neutral safety switch and associated wiring). It could also be a problem with the relay itself, the high current wires to the starter or the starter itself. Follow 67 darts advice and get back to us. It should be a simple fix.

Okay so I have grounded out the nss terminal and the issue was still there. From there I changed the relay and still no change. I’m pretty sure the only two things left to check are the ignition switch and the starter solenoid. I have a spare 96 5.9 style 5.2 mini starter. I’m thinking I’ll just switch it out and see if that solves the problem. Let me know if you have any other ideas. Thank you

 

[67Dart273]

Okay so I have grounded out the nss terminal and the issue was still there. From there I changed the relay and still no change. I’m pretty sure the only two things left to check are the ignition switch and the starter solenoid. I have a spare 96 5.9 style 5.2 mini starter. I’m thinking I’ll just switch it out and see if that solves the problem. Let me know if you have any other ideas. Thank you

STOP THROWING MONEY AND PARTS at the car. Follow some of the advice here and some that I posted. Learn to troubleshoot. If you don't have one buy a multimeter and a 12V test lamp. While you are at it, scare up some alligator clip leads so you can jumper stuff.

Did you download a service manual or wiring diagram? What have you tested? This type of problem is usually pretty easy to run down

Identify which wire goes down to the transmission, did you do that? It will be one of the two "push on" connectors on the starter relay and should be a dark color, usually brown. It goes down over the bell housing and heads to the transmission.

Disconnect that wire and ground the terminal on the relay you disconnected. The thing should crank with the key. If not, put a voltmeter or light on the wire remaining on the other push on terminal at the starter relay. This should should show power when the key is twisted. If not, move down to the connector coming out of the column , a long slender connector a single row wide. Look for damage. Probe that (yellow) and see if you have power there when key is in "start."

 

[jakeborg69]

Hey sorry for the update I took pictures and did trace it out Found some interesting stuff. Don’t have a buddy to turn the key for me right now but I traced out the wires and found some fuckery

 

[jakeborg69]

I’m guessing someone else had this issue back in the day and decided it was easier to jump the relay with a push button. I’ll trace out the rest of the wires and get back to you soon

 

[jakeborg69]

The push button was tucked up in the dash and wrapped in tape.

 

[Frank Mopar]

Ok so that's bad advice. He needs to figure out what the relay is not getting first then maybe it's a problem further back toward the ignition switch or maybe it's a problem with the ground side of the relay (neutral safety switch and associated wiring). It could also be a problem with the relay itself, the high current wires to the starter or the starter itself. Follow 67 darts advice and get back to us. It should be a simple fix.

The first thing you do with electrical problem before you pull out the meters and jumpers is verify connections and you think that's bad advice? Ok.

 

[Mattax]

I’m guessing someone else had this issue back in the day and decided it was easier to jump the relay with a push button. I’ll trace out the rest of the wires and get back to you soon

The first clue - or question - should have been "what is that extra wire doing on the relay's solenoid terminal?"

You have two choices in tracing the wires.
1. Unwrap everything and physically follow it. Draw out what you find.
2. Use your multi-meter to identify what connects with what.

In reality, the best method is a combination of these. This what I and some others were trying to get you to do up at the top.
a. Identify and draw or mark all of the components and connections of the relevant circuits.
b. Use the multimeter's voltmeter and resistance functions as appropriate to figure out what connects vs what should connect.
c. Then hunt down the circuit where connections should be getting made and aren't.

Seems like you are struggling with how to make use of the multimeter. I tried to give you a very step by step in post 13 to determine if power is making it from the key switch to the starter relay. Should not need a second person. Place the meter where you can see it and run the test leads as needed.

Two more tips.
a. When checking for resistance and continuity, disconnect the car's battery.
b. Remove the negative cable first, and while you're there clean the contact surfaces of both battery cable clamps and terminal posts.

 

[moparmandan]

The first thing you do with electrical problem before you pull out the meters and jumpers is verify connections and you think that's bad advice? Ok.

Evidently there's two schools of electrical troubleshooting. I went to the one where you understand EXACTLY what the problem is, before you take ANY steps to fix it. JMO.