DK40HST Won't Start.

[Billrog]

Check the starter relay you should hear it click when you turn the key on if it's failed there will be no click which is quite loud.

 

[Coyote machine]

So, I received my new parts from the dealer. (relay, key switch and cruise module) The dealer had me replace the relay and Module first, Ran it for a while doing work and FAIL. Shut it of and tried to crank over, no crank. Then I replaced the key switch. Couldn't run it because of work and weather. Ran it yesterday getting ready for a storm, shut her off after a while and NO CRANK. This is getting old. I think I am going to have to take her to the dealer which is 120 miles away. Anyone else have anymore ideas???

Nick

When you go to start it COLD, first start of the day, and you put the key to glow plug position do you hear a loud click?
When you go to start it after it has run and is up to operating temperature, do you hear the same loud click BEFORE you turn the key to crank position? Is there any cranking, even without starting if you put the key through a complete cycle from off to crank? Or is it just dead, no click and no crank regardless of how many attempts when the engine is up to temp?
Were all the dealer supplied parts new, unopened parts, or were some just spares he had on hand?
Does your temp gauge show a 'normal' temperature after running long enough that it should show the operating temp?

 

[MinnesotaEric]

I'm lazy and didn't read any of the thread so as to not pollute my mind with ideas.

1) has anybody used a test light or a volt meter on anything yet or has it all been guesswork?

2) After a failure to start, has anybody taken a hammer an rapped on the starter?

A test light will confirm if power is being sent to the starter and can be rigged to be seen from the cab.

A hammer will cause a deadspot in the armature or stuck relay to move or rotate to a non-deadspot and suddenly, without explanation, the starter will spin.

Diagnosing wise we should try to start at the thingy that isn't working and then work backward from there. Therefore, no start and you've got all the safeties set and ready to start, we first confirm power or a lack of power to starter. If no power, you move your test light and look to what can send power (the switch and relay). Then move to check continuity across all the safeties that can interrupt power with an ohm meter or test light.

If an open in the start circuit happens when warm, it can be an electrical connector at a component or more likely some silicon that controls the start circuit has failed. If unable to test, then inspect for a pin pulling out of any connector in the start circuit and unplug and plug the connector several times. The idea is that if corrosion is the issue plugging it in several times will scrape the corrosion off. Once satisfied that what you can see and do is fine, then give the hairy eyeball to anything silicon in the start circuit which is to say anything with a circuit board.

 

[Coyote machine]

A few other things to verify when the tractor is up to operating temperature. Have you tried moving the range selector lever from one neutral to the other and then see if she will crank?
Also you need to do a voltage drop test on the battery when it's hot. One other thing to do is take a pair of jumper cables and use just the negative cable; connect one end to the bolt on the factory negative cable where it attaches to the tractor frame, and the other end to the negative post clamp of the battery. If doing so makes the engine crank then you need to replace the entire negative cable with a new one. If not, at least you've eliminated a bad cable from the troubleshooting process. The same condition could be the case with the positive cable, but most often, if there is a problem it stems from the negative cable.
Less likely but still possible is your battery is dropping it's state of charge when it's hot to below where it has enough voltage to crank over the engine. When allowed to sit and go back to being cooler it then has enough reserve to crank it over.

 

[ritcheyvs]

Hey guys, go back and read post #1. The tractor starts fine if he jumps the contactor pins in the start relay connector. So the battery, cables, and starter are not the problem. The start relay is not the problem (tried new one and glow relay). The key switch is not the problem (tried new one from dealer). The neutral light is on so at least the cruise module thinks it's in neutral. The cruise module is not the problem (tried new one from dealer). As far as I can tell, the only things left are wiring harness and harness connectors. Considering Kodiak's saga, harness issues are possible: http://www.tractorbynet.com/forums/kioti-owning-operating/326616-no-hibeam-lobeam-ck-30-a-2.html#post3969089.

The only simple thing remaining IMO, is to disconnect, inspect, grease (dielectric grease), and reconnect the main wiring harness connectors. Unfortunately, the workshop manual does not do a good job relating the schematic to physical wire bundles and connectors. And you really don't want to open wire bundles unnecessarily.

This is a new tractor under warranty but the dealer is not close. Since the problem is fairly repeatable I think it's reasonable to use the warranty Nick already paid for.

 

[murphy1244]

Start at the key switch and work your way out from there. Power in and power out.

 

[ritcheyvs]

For James, Murph, CM, and others tracking this. Is it possible that the cruise unit inhibits engine cranking if it sees 12v on the alternator wire (because it thinks the engine is already running)? The EX documentation I have doesn't say this but I think it's possible. The lack of the battery light, when Nick turns the key switch to "on", implies the small alternator terminal (circle 2 in the big schematic) is closer to 12v than ground and that may be what's preventing cranking (via the cruise module). This could be caused by a fault in the alternator voltage regulator that "opens up" when it gets hot. This feature (no crank if 12v on alternator wire) is speculation on my part but it seems likely. What do you guys think?

For Nick, If you want to troubleshoot some more, next time it won't crank when hot (and the battery light is off with key on), measure the voltage (to ground) on one of the the small terminal on the back of the alternator. The alternator has one big threaded stud that is hard-wired (through the big 60 amp fuse) to the battery and two small spade terminals with a slip-on connector. One of the small spade terminals will be at 12v whenever the switch is on. We are interested in the other small spade terminal. I think it should be near zero with the key on, normally. In fact, do this same measurement when the engine is cold (key on and the battery light is on) to see if it changes whrn the problem occurs. If the voltage is near zero when it will start and near 12v when it won't I suspect your alternator (specifically the voltage regulator or an internal connection) is the problem (and I take back everything I said about wiring harnesses and connectors).

 

[MinnesotaEric]

Hey guys, go back and read post #1. The tractor starts fine.

Except when it is hot and when cold, he must key on and then jumper the starter and since we don't know how the starter gets its power it may have a bad relay, bendix, armature, whatever. I'll stick with the steps I outlined including a hammer as diagnostic tool.

Experience tells me that a silicon circuit has failed is most likely.

 

[Coyote machine]

Hey guys, go back and read post #1. The tractor starts fine if he jumps the contactor pins in the start relay connector. So the battery, cables, and starter are not the problem. The start relay is not the problem (tried new one and glow relay). The key switch is not the problem (tried new one from dealer). The neutral light is on so at least the cruise module thinks it's in neutral. The cruise module is not the problem (tried new one from dealer). As far as I can tell, the only things left are wiring harness and harness connectors. Considering Kodiak's saga, harness issues are possible: http://www.tractorbynet.com/forums/kioti-owning-operating/326616-no-hibeam-lobeam-ck-30-a-2.html#post3969089.

The only simple thing remaining IMO, is to disconnect, inspect, grease (dielectric grease), and reconnect the main wiring harness connectors. Unfortunately, the workshop manual does not do a good job relating the schematic to physical wire bundles and connectors. And you really don't want to open wire bundles unnecessarily.

This is a new tractor under warranty but the dealer is not close. Since the problem is fairly repeatable I think it's reasonable to use the warranty Nick already paid for.

Hate to disagree with you on this Scott, BUT, the cables to and from the battery to the chassis and to the starter are all part of what needs to be ruled out via troubleshooting. I've read this thread through from one end to the other several times and the things I haven't seen verified to date are what I've already outlined several times, or made queries of the OP, some of which have not been answered yet. We don't have actual battery condition established, specific gravity, load test, voltage drop, etc. We don't know what the PTO switch is doing when the tractor is hot, same with moving the range selector to the second neutral position to see if the 'pot' (switch) is flakey when hot.
What we seem to know is neither the ig switch, the cruise module or the relay has effected any change to the hot start issue.
Yes it starts when the start relay is removed and the pin sockets are jumpered, which would, to me at least indicate a possible lack of a solid 12 volt connection necessary to energize the relay when the tractor is at operating temp. This might point to a weak spot in the harness, or at a connector on the harness, as has been speculated.
So, I'm with you on the dealer solution to the problem, largely because, as usual, none of us are there to use the actual schematic and tractor along with proper test equipment to determine where the actual faults are located.
I have lost track of whether the tractor starts cold without any relay removal or pin jumping - can the OP please clarify that? I can't go back again to verify this point. Thanks.

 

[Coyote machine]

Except when it is hot and when cold, he must key on and then jumper the starter and since we don't know how the starter gets its power it may have a bad relay, bendix, armature, whatever. I'll stick with the steps I outlined including a hammer as diagnostic tool.

Experience tells me that a silicon circuit has failed is most likely.

It is when the tractor is HOT that he has to remove the relay and use the jumper across the pins. The relay has already been replaced with a new one, no difference in symptoms. There is no need to hit the starter with a hammer since jumpering the relay makes the tractor start without any other intervention. That is not to say there is not something 'off' with the starter, when the tractor is hot, for instance an internal binding of a bearing or similar. But what explains the ability of jumping the relay overcoming the starter's 'fault' without any other intervention?