Having some issues with my new toy, MC21 SP

The powervalves were not moving at all I noticed when changing the coolant and blipping the throttle

I did the test by disconnecting the tps and turning the bike on to see if the servo moves to high position but it stayed put, battery output 12.49v

I checked at the pgm unit harness on the harness side the BU/G-Y/R and it was within range (was 5ohms)
I checked between BU/G-Y/BU for resistance as I moved the throttle and was within range, so I can safely assume the tps is fine.

I tested the servo motor at the connector by applying voltage and it moves, also checked resistance between LG connector and the BU/G on the connector and fluctuates between 0 and 4.6 or so as the servo cycles.

now that the cables are off the servo I checked the movement of the valves by hand and they move freely

Next step was to check continuity between the black harness connector and the servo connectors...all good so harness is fine..

Output voltage at servo motor, ignition on kill switch on is 4.59v, seems fine...
Voltage at tps connector is 4.5

My manual says to check the output voltage from the black harness connector on the B/W to ground with ignition on and kill switch OFF, page 24-67. Says I should get battery voltage with switch off....I do when i put kill switch to run....but no voltage when switch is off....seems weird to me.

Anyway, what can I do ....what haven't I done?

gremlin in the loom? Have yo moved the servo out of position (e.g. bke off, fully open RC valve) an seen if it moves?

The other option would be to inject a voltage down the loom from the PGM connector to see if that will make it move.

Yea I did move the servo, it doesn"t do anything, unless I power it directly.

I did check continuity down the loom from the PGM3 end to the servo and its good as well.

When I follow the flow chart in the manual it says the CDI unit coupler is faulty...not even sure how to read into that...connections seem fine, plugs in nice and tight.

I just don't get it..

can I check continuity in the PGM3 itself or something..??

I would power the RCvalve down the loom from the PGM connector. You may have continuity, but you may also have the gremlin.

Failing that, you could try a new PGM? Get the PGM out of the bike and see if there is any burns/damage to the plastic case, see if it smells like burnt electronics.

Try your PGM on another known working NSR before you fry another PGM on your bike.

The usual story is that the transistors fail inside the PGM, so the RC valve servo doesn't operate.

This is resolved with either replacing the transistors or the PGM. Obviously the first is the cheaper option, but not easy.

Before just throwing on another PGM you need to know why this one failed. Check that the servo motor is free to turn smoothly and that the cables slide freely in the sheath. Also, that the RC valves are able to move from fully closed to fully open. Manytimes this problem can be traced to carbon build up behind the valve stopping them from fully opening. This overloads the transistors, which then fail.

firstly, thanks for your input fellas

I will run power from the PGM end to the servo tonite to see if there are any gremlins.

I can't check my PGM in another NSR as mine is likely the only one in my whole province...yay for being unique

Would all of the tests the manual says to do still work if the PGM was bad??

This part in my manual has me confused too..

My manual says to check the output voltage from the black harness connector on the B/W to ground with ignition on and kill switch OFF, page 24-67. Says I should get battery voltage with switch off....I do when i put kill switch to run....but no voltage when switch is off....seems weird to me.

Should I get voltage with the switch OFF... seems not right .I get voltage when kill switch is on...doesn't a kill switch kill voltage not allow it?

Also, how can I check the valves for carbon buildup? do I need to take the cylinders off??

nxrsr20 : I have powered the servo motor from down the loom at the 16pin connector end and the servo spins fine.

the only items that don't make sense withe th manual is the voltage output at the throttle sensor and saervo motor connectors. it was 6.82v on both and the manual says 4-5v.

Also in the manual it is a bit vague but says when i power the servo motor direct it should spin "opposite direction" I assume that is counter clockwise, mine just spins clockwise.

With CDI connected the throttle sensor has voltage and varies from .84-4.69v which is within range.

does that fact eliminate a potentially faulty CDI(PGM)Doesn't smell burnt either.

No NSR's within a few thousand kms to test on !!!!!

Thanks in advance for anyones help

I am about to install a new PGM, can someone tell me how to check if the servo-motor is ok or not, because I think I checked all the rest....
Also valves turn freely and motor turns as well. I just want to make sure that I wont burn the new PGM ( got it burned allready. someone just fixed power-valves in high postion with a screw)
thanks

I would do the following:

- See if it able to move the actuator into a different position by hand.

- Smell the servo and see if it smells like burnt electronics.

- Look at the wiring diagram and put power on the servo to see if it moves.

If it can't do any of the above, time for a new servo.

I am really bad with electrics...just looked at the diagram cant figure out where to connect the - and the + to see if the servo works, can anyone tell me?
Thanks

sounds to me like every thing is fine if you can power up the servo from the black connector and it moves im no pro with nsr wirring but i am a auto electrition
and looking at the wirring diagram it seems the servo motor uses two wires the W witch id guess is white and W/R witch at a guess would be white with red trace the pgm must switch the pollarity to change the direction other wise it has a earth on the motor itself witch would mean that the W an W/R are both powers with a common earth switching power from w to w/r would change motor direction if this is the case.
it appears the other wires going to the servo are to tell the pgm were the servo is in its range of travel .
anyway if you can power the servo and it works the fault must be in the pgm or the input signals it uses to control the servo.
eg. maybe the servo motor works fine but the sensor inside is telling the pgm its at full open or somthing silly like that.
i have two working servo's so if you have anyway of testing yours i can compare your readings to my good one.
als0 my mc21 wont cycle the power vavles with the old key on unplug tps trick i dont know why but it will at 2500rpm so i set mine up with the hrc 10000 rpm trick.
_________________
"Batmans a scientist"