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**bybowtie** · 05-14-2003, 09:00 AM

I am sure earl will get to you, but you can check a post from earlier in the forum that discusses the same thing.. you should have equal voltage but no more than battery voltage

**Anonymous** · 05-14-2003, 03:21 PM

checking voltage at coils

Ok.. I did a search of the forum on coils and voltage and saw that there should be over 11 volts at the coil connection. But the method described to check was to put your multimeter postive lead at the positive lead to the coils and your negative lead to ground or negative of battery. I haven't done that yet (will when I get home.. some people have to work

for a living).
(but then again I can sneak onto the internet now and then

)

I had checked with my leads of the multimeter at the positive and negative leads of the coils themselves. That's when I saw 9.5 volts at one coil and nothing at the other. I wanted to know if this is normal.. i.e. a reading between the terminals of the coil, rather than at ground.

**Anonymous** · 05-14-2003, 05:01 PM

The negative lead at the coil is grounded through the igniter when it sees fit to do so. If your one coil is not firing then checking positive to negative will not give you any reading at all. It must be tested from the frame or battery negative and to the coil positve, to give you a true reading.

Gavin

**Anonymous** · 05-14-2003, 05:35 PM

The way i understand it. when the ignition is turned on, the 12 volts or close to it is applied to the positive side of the coil. The way to test this is to use a multimeter. connect the minus or ground to the negative of the battery or other known good ground and the positiv lead to the plus on the coil. This test will only tell you if the coils are getting the proper voltage.

**Anonymous** · 05-14-2003, 05:38 PM

Originally posted by Shafer

The negative lead at the coil is grounded through the igniter when it sees fit to do so. If your one coil is not firing then checking positive to negative will not give you any reading at all. It must be tested from the frame or battery negative and to the coil positve, to give you a true reading.

Gavin

please explain some more to me on how you are testing at the coil to see if your ignitor is firing. I want to do some sort of test on my yammy and wonder if i places a meter across the primary side and cranked the engine , just what sort of reading would mean what??

**Anonymous** · 05-15-2003, 12:52 AM

Coils

Yes coils are powered from the ignition & kill switch...so testing from the positive side of the coils to chassis ground should read a voltage very close to battery voltage.
The ignitor simply supplies a ground when ready to "fire".
A simple test of the coils firing or not is to VERY briefly ground out the negative side with a test wire. Do it very rapidly as in zap,zap,zap to imitate a "running" engine. If your concerned about drawing too much current. fan out the strands of the test wire so no more than a few strands will vaporize as you arc them across the negative post.( disconnect the line to the ignitor first).
You will see the pulled sparkplug fire......or not.
Rick........

**Anonymous** · 05-15-2003, 03:10 AM

Testing at coil for igniter response.

To check if the igniter is sending a signal to the ground side of the coil,

1. with a meter set on volts hook the positve lead on to coil neg and the negative lead to battery neg. The reading will go from about 6v to zero depending on your coil resistance.
or
2.Hook a meter up between the negative on the battery and the negative of the coil. with the meter set on ohm, if you have an analog meter the needle will bounce while cranking. (I don't like this one as much because if you have voltage on the positve and connect the negative to ground it will ignite the spark plugs. How good is your meter? Cheaper ones with low impedence will ignite the plug, and possible burn the fuse in the meter.)

I hope this helps,
Gavin

**Anonymous** · 05-15-2003, 08:06 AM

Re: Testing at coil for igniter response.

Originally posted by Shafer

To check if the igniter is sending a signal to the ground side of the coil,

1. with a meter set on volts hook the positve lead on to coil neg and the negative lead to battery neg. The reading will go from about 6v to zero depending on your coil resistance.
or
2.Hook a meter up between the negative on the battery and the negative of the coil. with the meter set on ohm, if you have an analog meter the needle will bounce while cranking. (I don't like this one as much because if you have voltage on the positve and connect the negative to ground it will ignite the spark plugs. How good is your meter? Cheaper ones with low impedence will ignite the plug, and possible burn the fuse in the meter.)

I hope this helps,
Gavin

Thats sounds good Gavin--Thanks a lot.--I was thinking that i might finally also get to use the old scope for something by probing at the negative side while cranking also.
What input impedence do you consider a save value for a meter not to be effected by number 2 test.

**Anonymous** · 05-15-2003, 09:47 AM

voltage at coils

Ok, I checked the voltage at the coils with negative probe of meter at ground and positive at positive of coils. With ignition turned on I am getting a 10.75 volts reading at both coils. Interestingly if I disconnect the igniter unit (red connector on left side of Gs1100gk) the voltage reading is 11.75. I lose 1 volt with igniter unit hooked up.

Is this normal? Did you guys who reported almost 12 volts at your coils have an ignitor unit setup or old points and condenser type?

Also, as stated earlier, when checking my coils with leads of multimeter at positive and negative leads to coils (wrong way to check), with ignition turned on, I see 0 volts on one coil and almost 10 on the other.. is the ignitor "ready to fire" on the one coil even without the motor turning?

**Anonymous** · 05-15-2003, 11:27 AM

Re: Testing at coil for igniter response.

Originally posted by Shafer

To check if the igniter is sending a signal to the ground side of the coil,

1. with a meter set on volts hook the positve lead on to coil neg and the negative lead to battery neg. The reading will go from about 6v to zero depending on your coil resistance.
or
2.Hook a meter up between the negative on the battery and the negative of the coil. with the meter set on ohm, if you have an analog meter the needle will bounce while cranking. (I don't like this one as much because if you have voltage on the positve and connect the negative to ground it will ignite the spark plugs. How good is your meter? Cheaper ones with low impedence will ignite the plug, and possible burn the fuse in the meter.)

I hope this helps,
Gavin

looks like im lucky gavin. the secondary winding on the coil is open and the reading on the primary side is way off. I did the test for the ignitor any way and it seems like a very valid test.

thanks again.

**Anonymous** · 05-15-2003, 08:07 PM

a little more info

Also, as stated earlier, when checking my coils with leads of multimeter at positive and negative leads to coils (wrong way to check), with ignition turned on, I see 0 volts on one coil and almost 10 on the other.. is the ignitor "ready to fire" on the one coil even without the motor turning?

The reason for the zero voltage on one coil is because it does not have aground source for your meter.
If the igniter does not recieve a signal from the pick-up coils the path has not been opened yet for the spark signal, but to ease wiring Suzuki makes the positive side of the coils hot from ignition power.

If my igniter was not toasted I would pull the plugs out, ground them just to see it when the ignition is turned on either set would spark. Just curious.

Gavin

**Anonymous** · 05-15-2003, 08:11 PM

Test light test idea.

Scotty,
I have another test for you to try on the igniter. Hook a test light up to battery positve on the clip end and put the point on to the coil negative. Crank the engine over. The test light should flash. Just a theory though.

Gavin

**Anonymous** · 05-16-2003, 12:59 AM

Re: Test light test idea.

Originally posted by Shafer

Scotty,
I have another test for you to try on the igniter. Hook a test light up to battery positve on the clip end and put the point on to the coil negative. Crank the engine over. The test light should flash. Just a theory though.

Gavin

I just gave that bloody thing away this morning((truly). I had it for 25 years and it was still in the original pakage. I never went for those things. I am a die hard simpson 260 analog user. I love to be able to watch a cap load up when im testing. I used that test light on an old beetle that i was fooling with lots of years ago. I will try that test with the scope and engine running, as soon as i get the coil replaced. Im up to my ears in expences with the tires, the stator and now the yammy not firing.

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