Suzuki DT140 EFI (2000) - testing electronics issue

[scops]

Have an issue with the motor shutting down going into safe mode and suspect stator/coils and/or sensors.

Idles perfectly but suspect the high rev battery charging coil is shot and is causing motor to go into safe mode when attempting to get on plane. Getting the "rev limit" light and "check engine" light.

So far i've checked compression (ok), replaced t-stats and water pump and put a new voltage regulator per a marine shop that checked it out and said likely regulator or stator issue. Still have same problem.

My Suzuki manual covers late 80's through early 2000's and the DT 140 EFI seems to be the odd duck. In the ignition and electrical systems section under DT 115/140 the wires/colors indicated for ohm checking the pulser coils, battery charging coil, condenser charging coil and gear counting coil don't match what i have coming out of the stator?

Does anyone happen to have the correct wire combinations/colors and ohm test specs to test this motor?

Thanks in advance for you help on this.

 

[scops]

Re: Suzuki DT140 EFI (2000) - testing electronics issue

Tried uploading screen shot of manual, but having issues with that.

 

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Re: Suzuki DT140 EFI (2000) - testing electronics issue

 

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Re: Suzuki DT140 EFI (2000) - testing electronics issue

 

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Re: Suzuki DT140 EFI (2000) - testing electronics issue

 

[scops]

Re: Suzuki DT140 EFI (2000) - testing electronics issue

So i found a couple of schematics that were for this motor and wire colors matched exactly, but the troubleshooting guide/diagnostic process listed in the manual was not representative of my motor 2000 DT 140 EFI. Specs/diagnostics on the DT 150 almost look right. At any rate, i checked Pulser Coil (320ohms), Gear Counting coil (210), Condenser Charge Coil- High (48), Condenser Charge Coil - Low (starts to read something and immediately goes to 1/Open), Injector Power Source (18). Looks like that Condenser Charge Coil is likely bad. If confirmed, does this mean that the entire stator needs to be replaced? Not seeing individual coil parts listed in the parts book, so i am assuming so. Any feedback would be appreciated. Thanks!

 

[lakensea]

Re: Suzuki DT140 EFI (2000) - testing electronics issue

A solid (not flashing) check engine & rev limit lamp indicates low voltage. If you determine you need a stator, new ones are $558 and are currently on back order. I have a used one I can sell you for $250.

 

[99yam40]

Re: Suzuki DT140 EFI (2000) - testing electronics issue

Ohms test is one test but I like to get the peak voltage readings to see what they are.
Make sure you use a DVA adapter if you do not have the peak reading voltmeter made for these ignition systems.

Seems like you would be having problems at low RPMs if the low charge coil was bad. Maybe you have them reversed and it is the high that is bad

 

[scops]

Re: Suzuki DT140 EFI (2000) - testing electronics issue

I thought the same thing too. But, if the LOW Condenser Charge Coil was failing at the high end of it's duty, maybe that would cause the motor to go into safe before it even got to the HIGH coil? Seemed counter intuitive though. Can you obtain peak voltage by simly putting a volt meter on the battery and seeing what the charge is when you rev motor?

Ohms test is one test but I like to get the peak voltage readings to see what they are.
Make sure you use a DVA adapter if you do not have the peak reading voltmeter made for these ignition systems.

Seems like you would be having problems at low RPMs if the low charge coil was bad. Maybe you have them reversed and it is the high that is bad

 

[99yam40]

Re: Suzuki DT140 EFI (2000) - testing electronics issue

No you need to test the ignition components with the proper equipment at the places the service manual tell you to

 

[scops]

Re: Suzuki DT140 EFI (2000) - testing electronics issue

The only tests the manual gives is to check that Ohms for each component are in spec range, if not it says to replace.

 

[99yam40]

Re: Suzuki DT140 EFI (2000) - testing electronics issue

Is this an aftermarket or Factory manual?

Should have peak voltage specs listed in the manual. measure where you did the ohm tests , but normally they list a test connected to the rest of the system and disconnected.
Being EFI maybe they just say to hook up to a computer.

 

[scops]

Re: Suzuki DT140 EFI (2000) - testing electronics issue

I read this and was wondering if my check of the Condensor Charge Coil may have been sending me down the "replace the stator": road when i should be looking at finding a bad ground (kill circuit also grounds the primary circuit)that may be causing low voltage as mentioned in the second quote? I guess i should check the kill switch and see if maybe that's causing low voltage?


"A condensor, or capacitor as they now call them today, will basicaly show an open circuit on an ohm meter. When you first connect the ohm meter's leads to both of the condensor terminals, the pointer will first indicate a low resistance by moving quickly to the right and then move slower back to the left, indicating a high resistance reading. The Ohm meter's internal battery is charging the capacitor. If you short the condensor terminals and check it with the ohm meter again, the same thing will happen. If you reverse the ohm meter connections to the capacitor, you will see a quicker or larger movement of the pointer before it returns to indocating a high resistance. The ohm meter first has to discharge the charge you just put into it from the ohm meter before it works like it did before.

The range you set the ohm meter on will have a lot to do with the exact response you will get. A mid range setting is always a good starting point, assuming you have a 20,000 ohms per volt or higher meter. Some little inexpensive meters are only 1,000 ohms per volt and the indications may not be as clear. A digital ohm meter is a little more difficult to use in checking a condensor and the older style ohm meter with the needle pointer makes the capacitor checking easier to interpret.

If you get no response at all upon connecting the condensor to the ohm meter, either way, the condensor is probably open. If you get a very low continous resistance reading, no matter which way you connect the ohm meter, the condensor is probably shorted. Always make these measurement's with the condensor disconnected from the points to avoid confusion with the rest of the circuot."


"CHECKING STOP CIRCUITS AND IGNITION KEY SWITCHES

Many outboards equipped with stop buttons or kill circuits. Some larger engines with electric starters also contain ignition switches. These must be checked if ignition system fails to produce proper spark.

In engine with conventional ignition system, kill circuit often just simple grounding switch. When pressed, switch shorts primary circuit to ground. Fault in switch or wiring will cause system to fail to produce spark. Can usually check kill circuits in conventional ignition system visually.

In electronic ignition system, kill circuit also grounds the primary circuit. Usually, only one end of capacitor connected to ground. When stop button pressed, both ends capacitor grounded. Current prevented from reaching, charging the capacitor. To determine if fault present in stop button or kill circuit, need to bypass kill circuit. Procedure used to bypass and check kill circuit of 25 horsepower or 35 horsepower is the following:

 

[scops]

Re: Suzuki DT140 EFI (2000) - testing electronics issue

I read this and was wondering if my check of the Condensor Charge Coil may have been sending me down the "replace the stator": road when i should be looking at finding a bad ground (kill circuit also grounds the primary circuit)that may be causing low voltage as mentioned in the second quote? I guess i should check the kill switch and see if maybe that's causing low voltage?


"A condensor, or capacitor as they now call them today, will basicaly show an open circuit on an ohm meter. When you first connect the ohm meter's leads to both of the condensor terminals, the pointer will first indicate a low resistance by moving quickly to the right and then move slower back to the left, indicating a high resistance reading. The Ohm meter's internal battery is charging the capacitor. If you short the condensor terminals and check it with the ohm meter again, the same thing will happen. If you reverse the ohm meter connections to the capacitor, you will see a quicker or larger movement of the pointer before it returns to indocating a high resistance. The ohm meter first has to discharge the charge you just put into it from the ohm meter before it works like it did before.

The range you set the ohm meter on will have a lot to do with the exact response you will get. A mid range setting is always a good starting point, assuming you have a 20,000 ohms per volt or higher meter. Some little inexpensive meters are only 1,000 ohms per volt and the indications may not be as clear. A digital ohm meter is a little more difficult to use in checking a condensor and the older style ohm meter with the needle pointer makes the capacitor checking easier to interpret.

If you get no response at all upon connecting the condensor to the ohm meter, either way, the condensor is probably open. If you get a very low continous resistance reading, no matter which way you connect the ohm meter, the condensor is probably shorted. Always make these measurement's with the condensor disconnected from the points to avoid confusion with the rest of the circuot."


"CHECKING STOP CIRCUITS AND IGNITION KEY SWITCHES

Many outboards equipped with stop buttons or kill circuits. Some larger engines with electric starters also contain ignition switches. These must be checked if ignition system fails to produce proper spark.

In engine with conventional ignition system, kill circuit often just simple grounding switch. When pressed, switch shorts primary circuit to ground. Fault in switch or wiring will cause system to fail to produce spark. Can usually check kill circuits in conventional ignition system visually.

In electronic ignition system, kill circuit also grounds the primary circuit. Usually, only one end of capacitor connected to ground. When stop button pressed, both ends capacitor grounded. Current prevented from reaching, charging the capacitor. To determine if fault present in stop button or kill circuit, need to bypass kill circuit. Procedure used to bypass and check kill circuit of 25 horsepower or 35 horsepower is the following:

 

[scops]

Re: Suzuki DT140 EFI (2000) - testing electronics issue

Does anyone think a bad ground in the kill switch could cause low voltage in the system and if so, is there an obvious way to check this?
Thanks!

 

[scops]

Re: Suzuki DT140 EFI (2000) - testing electronics issue

Okay, so what i thought was an official Suzuki Shop manual wasn't. Ordered the exact manual from Browns. Peak voltage test is requiring plugs removed, a 2-pin/6-pin test cord, a 12v/100Ah fully charged battery.

Questions:

Why do i need a 100 Ah battery and will my 600 amp cranking battery blow the test? If so, where do you get a 100Ah battery? ALso, are these test cords basically keeping the system together and you're just getting pig tails to read off of? is there any way to make up a test cord or tap into the wires at the connector?

Never used a peak voltage meter/don't have one. Any reccos on makes/brands that are good and easy to use would be appreciated. Sounds like this is going to be a two person operation? Do you just hook up to correct wires, crank and the info is captured and displayed?

Thanks again for your replies. -sp

 

[99yam40]

Re: Suzuki DT140 EFI (2000) - testing electronics issue

Get a DVA adapter ( less than $100)or make one and the use a regular meter.
Look at post 23 in this thread, I made one like it and it read withing a volt or 2 of a meter I borrowed from a shop.
http://forums.iboats.com/showthread.php?t=219458&p=1473584&viewfull=1#post1473584

Maybe the 100ah is just a minimum.

I back probed the connectors with a small diameter stiff wire ( straight pin or paper clip)being careful not to puncture the insulation. Hooked meter leads to them and cranked over

 

[scops]

Re: Suzuki DT140 EFI (2000) - testing electronics issue

Hey Thanks 99yam40 for the info. i will give that a try.

 

[Ldavidgrover]

Re: Suzuki DT140 EFI (2000) - testing electronics issue

On these DT motors if you have one bad battery running even though the motor started it will throw some funny things at you. Also Make sure you have the right spark plugs installed. Running plugs without resistor with have you pulling you hair

 

[scops]

Re: Suzuki DT140 EFI (2000) - testing electronics issue

Hey thanks for the heads up LDG. i am running the BR8HS-10 plugs and battery checks strong. Replaced the battery connections as well.
Ordered a DVA, so when that comes in i'll hopefully have strong evidence as to what my real issue is. THanks again.