Kymco People GT 300i ABS No-Spark Issue – Need Advice on Troubleshooting

[angeloK]

Hi everyone,

I recently bought a Kymco People GT 300i ABS with a no-spark problem. The previous owner took it to a shop where they ran some tests and attempted to check the pick-up resistance (I can tell because they exposed part of the wiring). They convinced the owner to buy a new CDI, but it didn’t solve the issue.

Base Info:

• The engine is turning, and the starter motor works without any issues.
• The fuel pump is functioning but is currently disconnected.
• The battery is dead, so I'm jump-starting it using a fully charged car battery (13V).

Here’s what I’ve done so far:

• Confirmed the side stand is in the correct position and the engine stop switch is set to “ON.”
• Replaced the spark plug – still no spark.
• Tested the ignition coil resistance:
• Primary: 4.4ohm (manual states 3.57ohm - 4.83ohm)
• Secondary: 15.4Kohm (manual states 10.42Kohm - 14.49Kohm) – slightly out of spec.
• Checked the pick-up CPS resistance: 117ohm (manual states 115ohm ± 15ohm).
• Verified continuity according to the wiring diagram (attached).
• Inspected the tilt sensor, and each wire has continuity according to the diagram – Is there a way to bypass this for testing?
• Checked the engine stop switch at the relay end – it seems to switch correctly.
• Confirmed continuity between the ignition coil and ignition relay (both wires).
• Cleaned and checked ground connections on the chassis.
• Tested the stator phases – no shorts.
• Confirmed continuity from the stator to the rectifier and to the ignition switch.
• Tested the rectifier following a guide on YouTube – it seems okay.

Next steps:

• Measure voltage at the tilt sensor when the key is ON.
• Open the carter to inspect the stator.

Questions:

• What could be causing the no-spark issue?
• Which components could be bypassed to simplify the circuit and isolate the problem?

Any advice or insights would be greatly appreciated! 

Thanks in advance for your help! 

[Ruffus]

@angeloK, welcome here!
Very thorough search already.

Sounds trivial but you didn't mention sparkplug cable?
Fuses all new?

I would:
-make a direct (temporary) cable between battery minus and engine (jump cable wth frogs)
-unplug, spray and plug this big connector between CDI and wiring harness
-take tilt switch off, bridge the cables
-unplug side stand switch and bridge
-ignition coil new?
-ignition coil cables (green and black?) in working order and connectors not worn?
-kill switch: open and bridge this white and green cable?
-jumpstart with a car "IDLING" to get more than 13.0 V on your scoots electronic
And always only ONE measure at a time!
See a dealer who has a DiagTool to borrow.

[angeloK]

@angeloK, welcome here!
Very thorough search already.

Sounds trivial but you didn't mention sparkplug cable?
Fuses all new?

I would:
-make a direct (temporary) cable between battery minus and engine (jump cable wth frogs)
-unplug, spray and plug this big connector between CDI and wiring harness
-take tilt switch off, bridge the cables
-unplug side stand switch and bridge
-ignition coil new?
-ignition coil cables (green and black?) in working order and connectors not worn?
-kill switch: open and bridge this white and green cable?
-jumpstart with a car "IDLING" to get more than 13.0 V on your scoots electronic
And always only ONE measure at a time!
See a dealer who has a DiagTool to borrow.

Thanks for the welcome 

• Fuses not new, but just checked, sanded and cleaned with contact cleaner and tested continuity: they all seems OK
• Ignition coil and spark cable not changed, since I assumed the former owner and the shop would have tried this first already
• didn't make the direct connection, just seen you edited the message 
• cleaned the CDI connector with contact cleaner and re-tested all continuity: OK
• bridged tilt switch, side stand switch and stop engine (kill) switch

After all these measurement and bridges and so, I tried to read voltage coming to the ignition coil while cranking: NONE. 0V DC

So I checked the pick-up - as said, impedance is 117ohm - and read 0.7VAC, without oscillation between 0V and 0.7V. Is this ok?

If not, any way to emulate the pickup signal for the ECU?

Thank you for your thoughts! It helps a lot.

[Ruffus]

Scratching head...
Since there is a new CDI, thats OK
I would take the syayor cover off and check the pickup cables.

For ignition coil I have my doubts, would renew the piece in one until sparkplug.

There where the pickup cables leave the engine, they brake sometimes in this rubber grommet...

Look at the wire harness once again and in this big
connector before CDI, check pins in there one by one..

[angeloK]

Scratching head...
Since there is a new CDI, thats OK
I would take the syayor cover off and check the pickup cables.

For ignition coil I have my doubts, would renew the piece in one until sparkplug.

There where the pickup cables leave the engine, they brake sometimes in this rubber grommet...

Look at the wire harness once again and in this big
connector before CDI, check pins in there one by one..

Thank you for your time, and your patience.

Maybe I wasn't clear enough before, the did TRY a new CDI, right now I'm stuck with the old one. I don't have a new one to try.

For ignition coil I have doubts too, but since it receives 0V from the CDI when engine is cranking, I put that out of the equation.

I'll check the pins of the CDI connector again, at the same time I'm trying to emulate the pick-up signal with an Arduino, let's see what's going to explode! 

Update: no news.
Tested the CDI connector, each wire has continuity as it should. Still no voltage at the ignition coil.
Tested voltage coming from the pick-up, but I read very low values (both AC and DC). I can't say if the multi-meter I'm using is able or not to read voltage at that frequency or if the pick-up doesn't send any signal.

I think it's time to open the pocket and purchase a stator + pickup