1993 Honda TRX300 No Spark

[TRX300 Deer Getter]

Hey all,

First time poster here.  I have a '93 TRX300 with no spark.  Measuring 100 volts pulsing at the coil then declining down to 90, 80, 70, 60 and so on.  I assume it's the coil.  If there's voltage to the coil then everything else should be in working order, right?

Thanks for your help,

Deer Getter

[TRX300 Deer Getter]

Anyone have any insight here?  

[Ajmboy]

Sounds like it could be the coil. They are cheap on Amazon, I would try and swap it out to see.

* Added ATV year and manufacturer to topic title.

[TRX300 Deer Getter]

Great, thanks for the advice

[Thelostsinner]

Im in a similar situation with my 200sx. Have you checked the ICM?

[TRX300 Deer Getter]

I haven't checked anything upstream of the coil because i'm getting voltage to the coil.  I just don't have a repair manual so I don't know what voltage i should expect.  I ordered a coil from amazon so if that doesn't work i'll start more diagnosis.   

[Thelostsinner]

I had a no spark issue and it ended up being a R/B wire that was not connected on the main harness - if you've shaken down everything else already might want to look for wiring gremlins.

[JSRinHSV]

I just fixed my 1993 Honda 300fw four trax.    Replaced the  i c m  ECM or what ever it is called.  Computer module.   Unit rides in a little harness right in front of the steering column.   Remove front cowling and replace  Very easy to do.   Was getting no spark.   Replace the module and bingo.  Cranked right up.

 

[TRX300 Deer Getter]

On 8/19/2018 at 9:04 PM, JSRinHSV said:

I just fixed my 1993 Honda 300fw four trax.    Replaced the  i c m  ECM or what ever it is called.  Computer module.   Unit rides in a little harness right in front of the steering column.   Remove front cowling and replace  Very easy to do.   Was getting no spark.   Replace the module and bingo.  Cranked right up.

 

Sweet, appreciate the insight.  I have a coil i'm going to try today, if that doesn't work i'll move to the ECM.  

[TRX300 Deer Getter]

On 8/15/2018 at 3:53 PM, Thelostsinner said:

I had a no spark issue and it ended up being a R/B wire that was not connected on the main harness - if you've shaken down everything else already might want to look for wiring gremlins.

Good call, there's always a chance Stuart Little got in there for a midnight snack...I'm hoping a new coil works for me, if not i'll download the service manual and move upstream to the computers and control modules.  

[Kirt]

I'm have the same issue so thanks for help. I'll look for wires that are chew on first.

[MtBob]

The little box up front is called a cdi module.A common problem on the older units.Just ordered one for a neighbor,a cdi box,new coil,as a package,less than 20 bucks from ebay.

[Jas]

Any luck? If it’s not your coil, put your cdi in a preheated oven on 225 for 10 minutes. Should make it work enough to test it.

[TRX300 Deer Getter]

New CDI box was the fix 4 years ago.  Got a cheapish one on Amazon and boom I had spark.  It’s ran great for these last 4 years.  Funny you asked about this as just 3 weeks ago I again had no spark.  Engine turned over and ran for a few seconds then died.  After some diagnosis I figured out I lost spark again and replaced the CDI box and that fixed it.  The bad CDI box had a crack in it with what looked like a pretty significant short on the circuit board.  I guess at this point I’ll just plan on replacing the CDI every few years.  Thanks for the oven tip.  At around $20 for a new CDI I just went for a new part.  Read into this issue this time and found that no spark on these machines is usually the CDI box and sure enough that fixed it for me.  Hope this helps others.  

[Mech]

Ha, that's crazy cheap.

At that price you could keep one in your tool kit..

[Jas]

I’m glad you were able to fix it easily. These old workhorses will still be going in 100 years if China still makes cdi’s 😂

[Gwbarm]

I have noticed that the CDI boxes for the older ones are dirt cheap, not so much on 2000 up models, one for mine is at 400.00.

[CRAZYKIWI]

They are old quads but bullet proof