How to know if igniter and/or coils are bad?

[rahlberg]

Is there a way to tell if your igniter or coils are bad? How much voltage should I be getting out of the igniter (I assume on the wire that feeds into the + on the coils)? Same as the battery?

If I'm getting no spark on either coil, and I have the relay modifcation (as mentioned on this board) on, is that an indication that both coils may be bad or that the igniter could be bad since that's what feeds the coils?

For reference, this is an 81 GS650.

Thanks

Russ

 

[tkent02]

The relay, and the electric power to the coils comes in on the + side of the coils. The points or igniter controls the - side of the coils, basically switches the ground on and off.

 

[rahlberg]

When I installed the relay, it worked great...for a couple days. Now nothing. So I'm wondering if it's both coils or the igniter?

One thing I have not done is replace all the wiring in the harness. But I have checked, cleaned and checked again all the connection and wires between the batt/switches/buttons/igniter/coils.

 

[doctorgonzo]

When I installed the relay, it worked great...for a couple days. Now nothing. So I'm wondering if it's both coils or the igniter?

One thing I have not done is replace all the wiring in the harness. But I have checked, cleaned and checked again all the connection and wires between the batt/switches/buttons/igniter/coils.

Bad connection on the stuff you installed?

 

[tkent02]

See if the +12v is still getting to the + side of the coils, maybe something you did came undone. Did you put a fuse in the circuit?
Maybe it blew.

 

[rahlberg]

Yhea, I'm getting 12.69V on the coils. 12.7V at the battery. There is a fuse in the relay circut (15A which is what my main is, although my ignition is a 10A). No Fuse is blown.

I checked all the connections on the relay etc.. and they're all solid.

I just did the igniter test that the Clymer manual specifies (i.e. simulating a 1.5V on the black/white wire and the brown to force a spark on the #3 and 4 plug). There was no spark. The manual says that if this is the case, the igniter is bad.

Is there any other way to verify this out or anything else I should be looking at?

See if the +12v is still getting to the + side of the coils, maybe something you did came undone. Did you put a fuse in the circuit?
Maybe it blew.

 

[rahlberg]

I also did the signal generator test and previously was getting the 60-80Ohm reading, but now I'm getting nothing on all three wires.

Cause of no spark?

 

[SPARKSS]

I also did the signal generator test and previously was getting the 60-80Ohm reading, but now I'm getting nothing on all three wires.

Cause of no spark?

Hello rahlberg. If I was looking at your bike, with what you've said so far, I'd want to confirm 2 things with respect to your ignitor INPUT testing. First, when you checked for continuity of the signal generator coils, was this done at right at the ignitor? Did you verify your ohmmeter first (I've seen many probs with leads not actually being plugged in far enough to ohmmeter problems due to measuring while voltage was present (in your case the bike should never be cranking over while checking this)......and every bit as often, people using auto-ranging meters whereupon a marginal connection and/or any of the other problems is aggravated by misleading readings - always use a selected scale if possible.

The second concern with the INPUT testing you've done, is related....if the 1.5 volt cell (was the voltage confirmed first?) was connected at, say, the end of the harness nearer the ignition generator coil, then you may be looking at a broken harness between the pickup (generator) coils and the ignitor, especially if you were also testing the generator coils at the ignitor end of the harness.

If you verify the above - IF the supply voltage to the ignitor (remember to check both + and -) is ok, IF the supply voltage to the ignition coils is ok (you said it was), if you see voltage on the negative side of those same ignition coils (proving that the primary windings are ok), and IF YOU DON'T SEE SWITCHING of the ignition coils (which can be verified with a simple test light quite effectively), then your ignitor is probably bad (probably.....making sure that any wiring between the coil negative side and the ignitor is ok as well).

It's a simple system......Based on what you've described, I'll assume that you have 2 generating coils connected in series with a 3rd, common lead, between the 2 - so you should see continuity between all 3 leads.....with half the resistance seen if measuring between the common lead and either of the other 2.

Make sense?

 

[doctorgonzo]

FYI, I have an OEM igniter for a GS1000 (if that's your bike or compatible). I replaced mine thinking it was bad (Doh!!!!!!!!!!!! $300.00 mistake)), and it wasn't. Tested good. I went ahead and put the new one on anyway.

 

[rahlberg]

Hello rahlberg. If I was looking at your bike, with what you've said so far, I'd want to confirm 2 things with respect to your ignitor INPUT testing. First, when you checked for continuity of the signal generator coils, was this done at right at the ignitor? Did you verify your ohmmeter first (I've seen many probs with leads not actually being plugged in far enough to ohmmeter problems due to measuring while voltage was present (in your case the bike should never be cranking over while checking this)......and every bit as often, people using auto-ranging meters whereupon a marginal connection and/or any of the other problems is aggravated by misleading readings - always use a selected scale if possible.

The Ohmmeter was connected properly. I checked and double checked to make sure I had continuity. I then started on the signal generator. The Clymer manual says to put one lead on the green wire (which I did at the connector) and ground the other lead. There should be a 60-80ohm reading. I get nothing. I have two other wires coming off this, so I check the brown one. Nothing. I checked the black/white one, and I get continuity. But this one seems to be a ground. I did this test on the end of the wire (at the connector) as well as directly on the signal generator. Same thing: nothing. So the generator is bad (according to Clymers)?

The second concern with the INPUT testing you've done, is related....if the 1.5 volt cell (was the voltage confirmed first?) was connected at, say, the end of the harness nearer the ignition generator coil, then you may be looking at a broken harness between the pickup (generator) coils and the ignitor, especially if you were also testing the generator coils at the ignitor end of the harness.

I did a continuity test from one end of the signal generator wire to the other side of the igniter connector and I got continuity. Did this for all the wires. I wanted to see if there was any discontinuity anywhere along the wire or through the connector.

I actually went through all the connectors to make sure I had continuity through each wire. All are good.

If you verify the above - IF the supply voltage to the ignitor (remember to check both + and -) is ok, IF the supply voltage to the ignition coils is ok (you said it was), if you see voltage on the negative side of those same ignition coils (proving that the primary windings are ok), and IF YOU DON'T SEE SWITCHING of the ignition coils (which can be verified with a simple test light quite effectively), then your ignitor is probably bad (probably.....making sure that any wiring between the coil negative side and the ignitor is ok as well).

For this, I'm not 100% clear. What do you mean to check + and - voltage to the igniter? Like I said, I am getting voltage to the coils. I turned everything on, dropped the red multimeter lead on the + and grounded the black, and I got what the battery voltage is. So it seems to me that power is getting to the coil. The other wire on the coil gets the signal from the igniter/signal generator, correct? How do you check this...other than for continuity?

If the signal generator is out, wouldn't that be the reason it's not firing? No signal is being sent to the coil to tell it to fire?

As far as your test light goes, can you explain this a little more? I'm not clear what you mean on it.

This is all really starting to drive me nuts, but at the same time, it's very interesting. Thanks for all the help so far.

Russ

 

[SPARKSS]

Hello Russ. It sounds as if you're progressing pretty good with your diagnostics (I apologize where I've gone over in detail what it sounds as if you did naturally - hard to know what people know and don't know when helping from a distance )

In no particular order - To check for coil switching using a test light (standard unpowered variety), connect one side to ground (preferably where the coils mount.....double check later to battery negative*) and probe the - side of the coil while cranking the engine over. With an operating ignition (either points or electronic control) you'll see the light winking on and off as the ignition system (points or electronic module) tries to switch the coil associated - of course check all coils in this manner.

Good work checking all your harnesses end-end (all wires). By verifying + and - at the ignitor, my intent is to prove that the ignitor has supply voltage available on the pins or wires it expects to see it.....if the ignitor power supply uses its mounting bolts for supply - then thats where the negative lead should go......if it's on a seperate wire then testing as close to the ignitor as possible (connector?) would be the best place. Obviously testing wiring can only go so far "up to" devices......a connector perhaps.....if it has flying leads then it becomes a little more limited in that respect.

You're correct, of course, in understanding that a valid signal generator input to the ignitor must be seen in order to cause coil switching to occur - on it's output. Your signal generator needs to have a pair of wires with this "pick-up signal" on it, arriving at the ignitor, for each pair of associated cylinders (assuming a double ended or wasted spark type of ignition coil). For a 4 cylinder engine, also using double ended coils, you'd need 2 signal generator inputs to the ignitor (this assumes typical and not all possible ways of doing this). For 2 signals to occur out of the pick-up (signal generator), you'd need a minimum of 3 wires.......2 coils each with 1 wire seperately, and 1 wire common to both.......4 wires (2 each seperately) could also be a possibility. This description assumes a mag-reluctance type of pick-up generator.....basically a magnet with a coil wound around it that "see's" a close-passing notch or projection on the flywheel etc. It's this type of pickup that 2 tests can be done........one a basic resistance or continuity test to see if the coils are intact........and secondly an AC voltage test, either with a meter or an oscillosope (my preference) to actually confirm output is available.

A slightly different, similar, type of pick-up sometimes used is 1 or 2 coils (as described above) wound around a steel core (non-magnetic) which look at a rotating magnet on the flywheel etc......this setup likewise generates a voltage in the coils and is tested the same way.

There are other types of pick-ups or signal generators used on engines that are not like the above - which require their own supply on a wire (and may use their own mounting screws for ground) and output a signal on a seperate wire. One type is a hall-effect switch often used.

Reason for saying all this is how you've described your CLYMERS manual tests. I wouldn't have expected to see a test for continuity from a coil to ground as indicating GOOD......so really I'd need to see an accurate wiring diagram / schematic to help you further with this.

Hope this doesn't confuse

 

[LarryA_Texas]

Is there a way to tell if your igniter or coils are bad? How much voltage should I be getting out of the igniter (I assume on the wire that feeds into the + on the coils)? Same as the battery?

If I'm getting no spark on either coil, and I have the relay modifcation (as mentioned on this board) on, is that an indication that both coils may be bad or that the igniter could be bad since that's what feeds the coils?

For reference, this is an 81 GS650.

Thanks

Russ

I'm pretty new at this myself, but did learn one important thing. I have the same problem you are having now. I took the igniter box off the motorcycle and opened it up. Inside the lid has a bad burn on it and there is a resister that is fried to crispy. (actually, it looks like a little tiny hot dog my wife has cooked)

I'm thinking I found my problem. But now I'm trying to figure out what the resister was supposed to be so I can solder a new one in it's place. My bike has a 4 lead instead of 2 from the signal generator like the earlier ons. It's an '83 GS850GL

 

[saddlewarmer]

see my pm to you. i'll get info as soon as possible

I'm pretty new at this myself, but did learn one important thing. I have the same problem you are having now. I took the igniter box off the motorcycle and opened it up. Inside the lid has a bad burn on it and there is a resister that is fried to crispy. (actually, it looks like a little tiny hot dog my wife has cooked)

I'm thinking I found my problem. But now I'm trying to figure out what the resister was supposed to be so I can solder a new one in it's place. My bike has a 4 lead instead of 2 from the signal generator like the earlier ons. It's an '83 GS850GL

 

[rahlberg]

I couldn't figure out what was going on, so the way I fixed this problem was I bought the Dyna S ignition (DS3-2) for it. I bolted it on, and it fired up (using the same coils). Worked perfectly. :-D

Russ