05mtnvipermod
New member
hey guys watched the site for a long time and finally need some help with my viper. i think i may have fried the wiring while trying to adjust the power valves. the gauge does the regular sweep and then it does it again, and again and again, doesnt stop doing the sweep at all. so i was wondering if anyone would be able to help me figure out if i could to swap the entire harness with one from a 02' that i have laying around or if i could fix the harness on my own. i know that the 02 doesnt have dcs but i was wondering if it would still work.
Thanks for any help.
Thanks for any help.
mod-it
Member
This is a long shot, but have you tried revving it up a little? If your idle is set too low, it will keep doing the sweep.
Did you make the jumper wire to set the power valves or something?
Did you make the jumper wire to set the power valves or something?
05mtnvipermod
New member
ya i made a jumper wire but put the wires on the battery backwards. the sled wont come out of sweep mode at all even if im screaming down the trail at wot.
sometimes the plug at the back of the gauge gets corrosion or loose...& I have heard some who jump the system with a home made unit fries the cpu/cdi or even the servo...take the servo cover off & see if the servo cycles (sled on stand-servo cycles on start up & beggins cycling around 69-7000 rpm)05mtnvipermod said:
05mtnvipermod
New member
servo isnt turning but its not the servo it must be the wiring. i tried another servo that i know is good and it didnt work either. ill have to check the gauge connection as i havent done that yet. thanks for the suggestion. i suppose what im really asking is there any wiring guru's out there that could tell me what wires it is i fried by jumping them with the battery hooked up backwards.
servo is activated by the cdi box, so you have most likely ruined the circuit in the cdi box.
I would pull your harness out from under the engine, and check for wear or breaks in the individual wires. They can act really funny when they open or short out intermittently. I have seen a couple do exactly what you suggest.
There are a few bend down clamps under the engine that the harness goes through, and a couple removeable zip ties up front. Take the plugs apart at the hood hinge area. I like to tie a string to the plug end, and pull it up from the carb side by the recoil. Just be patient and shine a light down under the engine to see what is going on.
Also check the harness on the hood itself.
The circuitry in the CDI is pretty hard to fry unless you hook it up to an alternate power supply. Even a dead short has a hard time pulling enough current to fry it. It is possible that reverse polarity with a significant power source might have damaged the CDI, but I would eliminate the wiring first.
UPDATE: I just reread your last post above. As Mrviper suggests, you may have fried the CDI by applying a significant power supply in reverse polarity. I haven't seen the logic sheet for inside the CDI since '03 (when Yamaha closed that back door to the internal tech site) so I can't remember what protection there may be in place.
I would also swap CDI boxes with a similar Viper (at least temporarily) to see if this addresses it.
There are a few bend down clamps under the engine that the harness goes through, and a couple removeable zip ties up front. Take the plugs apart at the hood hinge area. I like to tie a string to the plug end, and pull it up from the carb side by the recoil. Just be patient and shine a light down under the engine to see what is going on.
Also check the harness on the hood itself.
The circuitry in the CDI is pretty hard to fry unless you hook it up to an alternate power supply. Even a dead short has a hard time pulling enough current to fry it. It is possible that reverse polarity with a significant power source might have damaged the CDI, but I would eliminate the wiring first.
UPDATE: I just reread your last post above. As Mrviper suggests, you may have fried the CDI by applying a significant power supply in reverse polarity. I haven't seen the logic sheet for inside the CDI since '03 (when Yamaha closed that back door to the internal tech site) so I can't remember what protection there may be in place.
I would also swap CDI boxes with a similar Viper (at least temporarily) to see if this addresses it.
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05mtnvipermod
New member
i changed out the smoothing condensors and everything is perfect again now. thanks for the suggestions guys.
Just curious, what made you suspect them?
Yes, more info please
I have a viper I'm working on with the same problem. This one is an ER and I had heard that the tack might do this if the battery is dead.....can anyone confirm this. As far as the smoothing condensors go....as Ding asked....how did you suspect them? It totally cured the problem?
Madmatt
I have a viper I'm working on with the same problem. This one is an ER and I had heard that the tack might do this if the battery is dead.....can anyone confirm this. As far as the smoothing condensors go....as Ding asked....how did you suspect them? It totally cured the problem?
Madmatt
05mtnvipermod
New member
well i changed the cdi with one out of an 02 thinking it may work but it wouldnt run at all then, so i changed the relays still no change, so finally i changed the smoothers before i was gonna haul out the harness and check the resistance in all the wires. i basically just changed stuff till it worked lol.
A er viper will keep flashing the display and resetting if the battery is dead even though you started the sled. Simply replace the battery.
The guys problem here was hooking up a powervalve tester and reversed the currrent. looking at the wiring diagram i still cant see how it went into the smoothing condensors but hey, if thats what fixed it so be it, glad to hear ya got it fixed. thats an intresting problem/fix, I will have to remember that if I get a ER viper in that someone has tried to set the powervalves with a tester instead of turning down the idle under 900rpm.
The guys problem here was hooking up a powervalve tester and reversed the currrent. looking at the wiring diagram i still cant see how it went into the smoothing condensors but hey, if thats what fixed it so be it, glad to hear ya got it fixed. thats an intresting problem/fix, I will have to remember that if I get a ER viper in that someone has tried to set the powervalves with a tester instead of turning down the idle under 900rpm.
05mtnvipermod
New member
the pv may not have been working before i tried to clean and adjust them. i dunno just trying to make sense of it all.