Electronics

answer: c.d.i. is bad !. word from the wise, THAT YEAR MODEL IS A ONE-YEAR ONLY AS FAR AS THE C.D.I. GOES ?!. in other words..you MUST have a c.d.i. from another running 1986 trx350 fourtrax in order to work.

oh well, life goes on..lol. thanks for the input !.

Thread update: Since posting this morning... I have figured out the issue of why the left handlebar assembly is not talking to the ECM. Not to say there wont be something else once this is solved somehow but at least now I know the main problem. So I unplugged the 22p connector at the ECM and used my continuity tester to check the wires at that harness. Service manaul says you basically check continuity between red/black and white/blue as your pushing the up/down button and the red/black and yellow/white (don't remember which is up/down).... but with everything else plugged in and testing at the unplugged 22p harness at ECM, zero continuity for either button. So then I did the same testing but isolated the left handlebar assembly only and everything there worked perfectly. So then I tested each wire between the 22p harness that plugs into the ECU and at the unplugged harness where the handlebar assembly normally plugs in. I have continuity at the white/blue and also at the yellow/white but ZERO at the red/black. Since that wire is common for both the up/down switch it made a lot more sense why neither button would tell the ECM to shift gears.   So.... I either have a wire broken inside the harness OR where the wire/pin connects at one of the harness has a bad connection. I have checked everything visible very carefully and see no obvious damage so I am hoping its a bad connection at the pin since that is fixable. I am gonna do a little searching to see if there is any instructions on how to re-pin the connections. If its not that and the wire is broken somewhere there is no chance I will be able to pinpoint the break easily and would be better for me too just run another separate wire as long as I can find the correct pins required to do that. Any chance anyone knows which pins Honda uses and if that's something I can buy so I can fix it myself? Only other option I know of is too replace the entire harness which I hope to avoid. I havent seen the bypass kit yet so not sure if that solves this without me repairing the wires but my hope is that I can fix it back to oem now that I have pinpointed the problem and not have to use the bypass kit for the shifting.

Welcome to the forum Definitely some sun damage, a lot of time humidity will cause those to oxidize like that, depending on area of the country you are incircuit  About 75% of the circuit boards I see have some level of oxidation to the screws even if they working ok Does the card power up at all? LEDS all function etc?  I will need a few more details about what all you have going on with it I have sent my direct contact information to your message box as well -AKATV  

Shade/sdec40 That speedometer is definately for an 98-01 450S The LCD screen is the same for the 98-04 450S models even thru the addition the the extra LED for the 4x4, the circuit cards are different, but the displays will swap over The black looking ink type spots are a known issue, more particular to the 450S model screen for some reason It is not repairable and the LCD must be replaced sdec40 said he thought he was able to repair his black spot before it cracked, I have not seen, or been able to replicate any successful long term repair of this kind of damage. -AKATV