Starter Continues to Crank Until I Disconnect Battery

Tried to start in cold weather today. It sounded like it was going to start but the starter never stopped cranking with the motor trying to start. I turned off the key and went around, removed the seat and yanked a battery cable off and got it to stop cranking. Went back to make sure the ignition was truly off and it appeard to be so I tried to connect the battery again and got big spark melting the battery terminal a little. I disconnected battery and that is where I left it. The starter still seems to be engaged trying to crank.

How do I test the switch without the battery hooked up?
How do I determine if it is the solenoid or starter?

Basically I dont know the order/ method to troubleshoot without frying something. It's 24v

Do you have an aftermarket ignition switch? Those cause this.

First do you have a keyed ignition? If so that’s most likely your problem.

Second, if you don’t have a keyed ignition it’s most likely your solenoid. See above and get the rebuild kit.


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NDT said:

Do you have an aftermarket ignition switch? Those cause this.

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Yes a key ignition.

Dock Rocker said:

First do you have a keyed ignition? If so that’s most likely your problem.

Second, if you don’t have a keyed ignition it’s most likely your solenoid. See above and get the rebuild kit.


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Yes it is keyed. Can I replace with an original switch or did I ruin the starter/ solenoid as well?

ebay ignition switch

MNINENINEEIGHT said:

Yes it is keyed. Can I replace with an original switch or did I ruin the starter/ solenoid as well?

ebay ignition switch

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Toss the keyed switch. It will cause you nothing but heartache.

You may not have burned your starter up. I would put the factory switch back in the truck and hook it back up to the battery and see what happens.


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Dock Rocker said:

Toss the keyed switch. It will cause you nothing but heartache.

You may not have burned your starter up. I would put the factory switch back in the truck and hook it back up to the battery and see what happens.


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Good thanks. It came to me with the key switch, I will try to source one without a key.

unplug the wires to the key switch, if you still get big sparks at the battery, it's the starter solenoid, otherwise it's the key switch.

Most likely the key switch....The people out there that had these made up...had the cheapest chinese switch used and added the military connectors.

86humv said:

Most likely the key switch....The people out there that had these made up...had the cheapest chinese switch used and added the military connectors.

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that and they aren’t rated for 24v....

Coug said:

unplug the wires to the key switch, if you still get big sparks at the battery, it's the starter solenoid, otherwise it's the key switch.

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I took the switch off and the battery still sparks like a welder. So I guess the next step is replace the solenoid?

MNINENINEEIGHT said:

I took the switch off and the battery still sparks like a welder. So I guess the next step is replace the solenoid?

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That would be my guess, unless something else went wrong as well.

papakb said:

Disconnect your batteries and then remove the heavy gauge wire that goes to the starter from the stud on the starter. With an ohm meter measure the stud to the case of the starter. If you show continuity (0 ohms) then the solenoid has shorted out and needs to be replaced.

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I removed both cables but couldn't get a reading on the back post. I got a zero on the post in the middle and bolt on the side of the case, with both cables removed. Was this done correctly?

I attached a couple pictures but have had trouble before.

papakb said:

The middle post on the starter body is the system ground post and the cable coming from it should run to the shunt in the battery box. This post should read 0 ohms to ground. This is also the post that the supplemental ground harness connects to. If you don't have one installed in the truck I highly recommend one. They are available online but they're also easy to make up.

The rear post is the +24v from the batteries. This has a heavy strap on it that carries the starting current up to the solenoid and then into the starter when commanded to start. There should be no continuity from this post to ground if the solenoid is working properly. If the solenoid was shorted you would get a low ohm reading from that post thru the solenoid and then thru the starter windings. The fact that you do not get a reading there says the solenoid contacts aren't closed, which is correct.

Your next step would be to reconnect everything then find the 8 gauge wire marked 74A and disconnect it from the starter. Monitoring voltage on the 74A lead it should show 24v with the START command and then drop back to zero when the switch or key is moved back to the RUN position. If it stays at 24v then something in the control box is bad. The start command runs from the switch to the control box where it's checked to make sure that the batteries are connected properly and the truck isn't already running. If everything is OK then the signal is sent to the starter to engage the solenoid and start the truck.

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Sorry for the radio silence... Holidays/ Sick. Thanks for the help, I tested the wire and there was no mark on it but it was also connected to a small wire marked 74B so i guessed the other one was 74A (the other wires were labeled but no 74A). While key in run 24v continued to draw. I confirmed the starter works by taking off the shield and videoing the starter gear in action while I connected the battery. The starter gear goes out turns the flywheel and goes back in when the power is removed as would be expected. Does this confirm it is the control box that is the problem?

Is there an additional way to confirm it is the smart start control box? They are not cheap. Are these two the same? They appear to be the same with the same Diagnostic port and temp control.

The one that is currently installed is a KDS Smart Start System SOCN6500435
MFR.: 09HP0
CR-2700

There is one on ebay :
Nartron
19207SOCN12480779-1

What you could try is tap the solenoid with the handle of a screwdriver or a ratchet extension and see if it unsticks the solenoid. Sounds like that is stuck in the "energize" position. It might take a few "taps" with the screwdriver so keep trying. After getting it unstuck, I would take the starter off and the solenoid off and take it apart. Probably best to replace solenoid. Good luck. You'll get it fixed.

Valor said:

What you could try is tap the solenoid with the handle of a screwdriver or a ratchet extension and see if it unsticks the solenoid. Sounds like that is stuck in the "energize" position. It might take a few "taps" with the screwdriver so keep trying. After getting it unstuck, I would take the starter off and the solenoid off and take it apart. Probably best to replace solenoid. Good luck. You'll get it fixed.

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Thanks Valor, the tapping didn't change anything, I spent some time and took the starter out. Tommorow I will get into the solenoid and see what's up.

Got the solenoid open and the contacts appeared to be fused but don't know for certain. Second pic I wiped off some of the black. Will cleaning the contacts and reassembling be the best next step? I could connect it back to the wiring and test before installing. How do I know if it's toast?



Is the play in the spring end portion normal? It moves around but springs back.