Strange Trekker immobiliser/cdi issue

Hi all,
So, I have this 99 Trekker 100, it starts, runs and rides ok but the immobiliser led flashes all the time. I have the red key and the black key.
Weird enough but it has an erratic running problem- sometimes it cuts out at about 50 and won't restart. The coil/ht lead looks good and quite new.
So to the cdi- it should be the aec400 type but it has a red mitsuba unit fitted, by just one plug and a ground (I think) the immobiliser isn't connected at all. The cdi is specified for several Piaggios, 4 stroke 125's mostly.
Could this cdi be the source of my occasional cutting out problem?
I was thinking of buying a bypass unit and disconnecting the immobiliser entirely, as it doesn't seem to be doing anything anyway.
Thanks in advance!

 

It sounds like somebody has already done a bypass on the immobiliser, it should have both connectors hooked up. Get the proper bypass unit for your model. If its the specific one to your model it will spark at the correct time etc etc and should solve your issues (hopefully) Sod the immobiliser off as its a pain in the bloody arse. If you want the light to stop flashing just disconnect it from the back (take the clocks out etc etc)

 

Hi guys, thanks for your replies.

Accyuklad, I contacted one of the cdi sellers on Ebay and one of their cdi's is on it's way to me now. Thanks for the tip!

Scootzmadness- I don't know a whole lot about cdi's or immobilisers but I would tend to agree with you that a previous owner has attempted a home made cdi bypass using something they found in their shed maybe. And how could it work if it's not designed for this ignition system?

I've disconnected the immobiliser and the scoot still starts and ticks over ok.
When the new cdi arrives I'll update with the latest news

 

they came in red or black those aec 400's , its possible they just swapped out a black dead one for a restock red version

 

It's not an aec400, it's a Mitsuba 2099.
The plug from the loom to the other connection on the cdi won't fit either, i.e the keyways are incompatible.

 

yeah its a piaggio model of the aec 400 buddy

 

Most engines are similar in the low end range with regards to mapping, Its only when it gets into higher range that it needs to really spark at different times (higher the rpm more sparking) the curve may be similar low end but could be out of whack top end and that COULD be why its bogging. My old Kymco would run off of a honda CDI well low end but wouldnt top end speed. It needs to be the right one for the right engine. There will be a slight difference between a CDI for a 125cc and a 100cc.. Its just best to have the right one for the right engine instead of having the wrong one in there.

The immobiliser system is actually very simple in theory. One chip in the key, Read by a piece in the ignition itself which then sends a signal to the CDI/Immobiliser unit saying, yes right key - power up. Red key will send a different signal to black key so on, so on. If a key doesnt read properly by the ignition, the ignition wont tell the CDI, yep its good and it wont fire up.

 

Haha! Ok! So it's nearly right

 

That all adds up, hopefully I'll be able to report back that the things sails away and hits 60 mph with ease ;-)

Thanks for the immobiliser rundown. No longer such a mystery to me

 

So an update on my problem-

I fitted the replacement cdi, finished a couple of other jobs that were waiting around and put the scoot back together this morning.
Took it for a decent little run of 25 km's and it was perfect! Once it was warmed up the acceleration was smooth and quick. I had 60 showing on the speedo with a bit of a downhill and there was no cutting out.
Success :-D

 

Grats David , i bet you were smiling like a cat after the inital will it wont it work.

ride safe and enjoy the open roads fella

 

You're absolutely right! :-D
It was cold and I wasn't really dressed for it as I only intended to buzz around the block a few times but you know how it is!

 

lol we sure do lol, that what is called a short buzz round the block ends up a full lap of the whole town and village and even then its like you just wanna keep on rolling but that little voice in the head says " we should really head back now " lol

 

You've just described exactly what happened

 

That red cdi works as an unlimited one for a tomos with a35 motor.... Glad you fixed it

 

The metalwork isn't standard for that model.
I got all the red bits and pieces with a parts bundle from ebay. The front mudguard piece is off a 50cc Streetboard model (I think) and the rear rack was possibly an optional extra. Some have them, some don't, it seems.
Some of them might come off, I'm not sure if I like it this way just yet.

 

I found it on Google listed for a few Piaggio models but didn't investigate further.
If anybody wants it they can have it FOC