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huffy

Need wiring help

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huffy

I'm trying to wire up the Command CH20S that I put in my Sunstar to replace the Magnum. But, I can't get it to work.Here's some pics of the pigtail coming off the motor:

engine pigtail 1.jpg

engine pigtail 2.jpg

The wiring configuration looks the same as in the "pinout" diagram that PhanDad posted in conjunction with his recent CH20S install:

Phandad diagram.jpg

So, I made my wiring harness to match what was coming out of the motor:

My pigtail - motor side.jpg

My pigtail - motor side and switch side.jpg

But, when I turn the key I get nothing. I've tried swapping the wires around to various configurations, but still nothing. Any ideas as to what I'm doing wrong?btw, I'm using the same 5 prong key switch from the Magnum engine. I assumed it would work with the Command. Maybe that's one of the problems?

57e059a8cd1d8_enginepigtail1.jpg.6b93e6975232a8a4230c673fed921670.jpg

57e059a8de421_enginepigtail2.jpg.7bf16d70e0fbfcda07b2aea587a84364.jpg

57e059a96daa2_Phandaddiagram.jpg.1f6c372dffbee015da1d3ad7229fa8a6.jpg

57e059a9803b7_Mypigtail-motorside.jpg.c88b25d69277b8d816d8fd5302e5e5b4.jpg

57e059a991a78_Mypigtail-motorsideandswitchside.jpg.0c449a480f9d04933b30fed92eac13c7.jpg

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Brettw

Check. There is a wire that is a ground wire. It is small, 16? gauge, and I found out that without it grounded, nothing happens. It is tied into the ignition circuit, key switch, not sure. But I had the same issue. Everything hooked up but nothing. Until this singular ground wire was hooked up. Then I was good to go. Might not be your case, but it was in mine.

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PhanDad

Did you try putting +12v directly to the blue start wire using a jumper direct from the battery? You don't have to have the plug connected for the test. I'm sure you have the battery grounded to the case of the engine. If using the jumper doesn't engage the starter, then the starter solenoid or starter is bad.

If the starter spins, then you're not getting +12v volts through your wiring harness; could be any of the interlocks or the interlock module itself if it has one. And also, like Brett stated, the interlock module usually has a ground input that must be good for the interlock to function and allow the start circuit to work. This light gauge ground wire is mentioned in my install post. (The reason this ground must be functional: it's the ground used by the dash mounted starter solenoid. If it's not a good ground, then even if +12v is applied to the solenoid from the ignition switch, there is no ground to allow the current to flow. No current flow, no solenoid action.)

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huffy

The battery ground cable is bolted to the frame, same as it was before I removed the Magnum.

Running a jumper wire straight from the positive battery terminal to the blue wire on the solenoid (or the blue wire in my harness) causes the solenoid on the motor to click/engage.

Running a jumper wire straight from the battery to the solenoid post opposite the one that you bolt the positive batter cable to causes the starter to spin.

By "interlock module," are you referring to the key switch? Mine does not have a ground wire coming off of it. There wasn't one on it when the Magnum was in. Maybe I need to add one?

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PhanDad

The interlock module is separate from the ignition switch. It takes takes the information from the various safety sensors (PTO lever position, operator in seat, etc) and decides what actions can take place (start) or not (engine won't run if blades engaged and no operator in seat). As far as I know, all 7100 series tractors have them, FDT tractors did not , late 7000 series might have them. I don't have any SunStar info so I don't know if your tractor has one. I seem to remember helping Brett with an interlock issue, but I don't remember what kind of tractor it was.

If you look at my Command install post, the wiring diagrams show the interlock module is the bottom right corner. You'll see it's wired into all the safety sensors. You'll also see it has a ground wire connected to it. That's the ground wire that has to be connected or nothing happens.

If you have a volt meter, check for +12v on ignition switch side of the dash solenoid when the ignition switch is in the start position. If so, then the ignition switch is good. Then check for voltage on the other side of the dash solenoid; if there's no ground it will also show +12v. You'll then know it's a ground issue.

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huffy

Ah, I should have explained . . .

The interlock module thingy and all the safety sensor stuff was long ago removed from this Sunstar. There also is no dash solenoid.

All that I intend to wire is the motor, headlights, and the front PTO. Right now, I'm just doing the wiring for the motor.

My thinking was that if I run the positive battery terminal to the solenoid post, and have the battery ground cable bolted to the frame like when the Magnum was in, I should essentially just be able to plug the key switch directly into the little pig tail coming off the motor and turn the key and start it up (kind of like you'd do if you were going to bench test it).

But, even plugging the key switch directly into the pig tail coming off the motor give me nothing. The key switch worked 2 days ago when the Magnum was still in, so I'm fairly sure it's not a bad switch.

I had thought that the switch was self-grounding (since it's metal and goes into the metal dash plate), because there was no ground wire running to it when the Magnum was in and because I don't see a post on the back for hooking a ground wire to it. That's why I'm wondering if maybe I need a different switch or something.

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GrincheyOne

Chris,

There is no ground post to speak of. There is a foil from the center of the switch, that is sopposed to be in contact to the switch case. In several switches, I have purchsed the foil nver makes it to the crimped edge of the shell, and I had to solder my own bridge between them.

Wayne

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huffy

I took the motor back out of the tractor and mounted it to my bench:

Motor.jpg

battery.jpg

Ground wire.jpg

I plugged the key switch into the pigtail on the motor:

Key switch.jpg

Again, turning the switch does nothing. I checked, and the part # on that switch is the same part # for the switch in my Legacy (same # stamped on both of them). I swapped out the switches, and that switch works in the Legacy. So, the switch is good. I started thinking maybe one of the wires is loose up inside the motor, so I took the cover off. All the connections up inside looked okay to me:

Under cover 1.jpg

Under cover 2.jpg

Under cover 3.jpg

Under cover 4.jpg

Under cover 5.jpg

Under cover 6.jpg

So, I'm stumped. Solenoid's good. Starter's good. Switch is good. But still nada. Anybody got any other ideas?

Motor.jpg.35007fccdbd409ad0b74a8b06127dd57.jpg

57e060b3bff0a_Groundwire.jpg.fb0eca31831dc483adce06228da8d33b.jpg

57e060b3d27be_Keyswitch.jpg.54b5f290e5cdad742774e6a6e65926b0.jpg

57e060b3e4975_Undercover1.jpg.5d8b2344e886a464f6da2c56ea24baab.jpg

57e060b406242_Undercover2.jpg.68df5498fe79efe04253b3d45af913f4.jpg

57e060b41c114_Undercover3.jpg.2bb7212b8a00fe8fb92ef41331548d29.jpg

57e060b42b90b_Undercover4.jpg.558ef3d328ca84e4ba6c59e51a437477.jpg

57e060b43c75f_Undercover5.jpg.1d38ff9c8099111ae0e36d06aff5f4c6.jpg

57e060b44e004_Undercover6.jpg.2f34f96b91023ae3785ab7823703fd0c.jpg

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BLT

Chris Magnum and Triad engines wire basically the same. Here is Triad to Command wire diagram. Extend main power lead from power side of existing starter relay to top post of starter solenoid. You might be able to reuse Magnum starter wire. That frees up post on starter relay. From that unused post of the relay make up a wire to run from it to the small flat tab on starter solenoid. That's all you have to do.

TriadtoCommand.jpg

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huffy

Bob: there is no existing starter relay. I'm not trying to wire it into the old system.

Basically, how it's set up on the bench is how it will be set up in the tractor. The only differences are that I'll add a lead harness from the pigtail on the engine to get the key switch to the dash, and I'll add a few wires for the lights and pto.

I don't understand why it's not working on the bench the way it's wired. I'm starting to think the oil sentry switch thingy is bad or something.

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PhanDad

Plugging the switch directly into the motor connector won't work because there's no +12v connected to the switch. AND more importantly, the pin-out connections might not be the same on the connectors and if you put +12v directly to mag's (kill circuit), it will fry them.

As I understand it, you are running the "start" wire directly from the switch to the engine connector, with no intermediate dash solenoid.

So, with the switch in the dash and connected to the battery, does the "start" position give +12v? If so, then the wiring to that point is OK. Next is there +12v at the connector end of the wiring when the switch is in start? If so, so far so good.

When you connect the plug to the engine, is there +12v on the engine starter solenoid? You can test this without the engine turning over by not having the +12v battery cable connected to the starter. You should hear the solenoid energize. If the voltage is low, the wire gauge used for the "start" circuit might not be large enough to meet the needs of the engine solenoid.

And again, I don't know Sunstar's with Magnum engines, but I would think that it had a dash solenoid since I never saw an earlier engine have it's own solenoid mounted on the starter. Unless the Magnum had it's own solenoid/starter, there must be one somewhere.

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huffy
quote:Originally posted by PhanDad

Plugging the switch directly into the motor connector won't work because there's no +12v connected to the switch. AND more importantly, the pin-out connections might not be the same on the connectors and if you put +12v directly to mag's (kill circuit), it will fry them.As I understand it, you are running the "start" wire directly from the switch to the engine connector, with no intermediate dash solenoid. So, with the switch in the dash and connected to the battery, does the "start" position give +12v? If so, then the wiring to that point is OK. Next is there +12v at the connector end of the wiring when the switch is in start? If so, so far so good. When you connect the plug to the engine, is there +12v on the engine starter solenoid? You can test this without the engine turning over by not having the +12v battery cable connected to the starter. You should hear the solenoid energize. If the voltage is low, the wire gauge used for the "start" circuit might not be large enough to meet the needs of the engine solenoid. And again, I don't know Sunstar's with Magnum engines, but I would think that it had a dash solenoid since I never saw an earlier engine have it's own solenoid mounted on the starter. Unless the Magnum had it's own solenoid/starter, there must be one somewhere.


id="quote">
id="quote">There was a solenoid mounted to the coolant housing. I took it off. I didn't see any need for it, since the Command has it's own solenoid.

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PhanDad

Here's the wiring diagram for a Sovereign with KT-17. I believe it uses the same the ignition switch:

16GTHL_Wire7117a.jpg

The pin-outs are different. Note the function of the single slot location. On the ignition switch it's +12v for the start circuit; on the engine connector it's the mag kill wire. That's how many coils get fried.

16GTHL_Wire7117a.jpg.f1cce0edb2595cfd7ad1699dbaa4b738.jpg

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CarlH
quote:There was a solenoid mounted to the coolant housing. I took it off. I didn't see any need for it, since the Command has it's own solenoid.id="quote">
id="quote">

It is a good idea to use a relay (or the original solenoid) to energise the Command solenoid at the starter. The Command automotive style solenoid requires considerable current to pull in reliably. The key switch alone will not supply sufficient current reliably over time.

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huffy

Bob, angel of mercy that he is, just spent about 1/2 on the phone 'splainin' some things to me. (Not the 1st time he's had to do this). I think I've got it figured out now. Tomorrow after work I'll implement Bob's instructions and give it a try. Hopefully I won't screw it up again.

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