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Discussion Starter #1
So for the folks who really understand the function of the DCT, what would cause this behavior ?

And, proper to ask, what happened recently that might have a bearing on this new challenge ?

I installed the McCruise cruise control, and it's computer needs various inputs from the bike in order to function - speed sensor tap, brake switch tap, to name two -- I don't know right off, what else.

And classic poor planning: I performed this mod just a week before my pillion and I were going to take an extended trip.

Thanks in advance.
 

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I have a feeling that you may have the answer to the question yourself. There is obviously some feedback loop between the electronic cruise control and the speed computer sensor. Disconnect the cruise control and see if it returns to normal.
 

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If I understand the problem correctly you put it into D, accelerate and it shifts into neutral instead of second? See page 23-3 wiring diagram top left corner. If they had you tie into the “ N-D SHIFT SWITCH ” light green/black wire this could be your problem. This wire goes directly to the PCM labeled “ SEL N ” . When you select N by pushing the button I believe the circuit is completed vie the red to Y/R to JUNCTION D to G/Y wire which the PCM interprets this as command to neutral. If by tying into this wire it is being grounded somehow through a loose connection or an issue with the cruise control it is going to shift to neutral. I’m guessing!!!
http://www.greenknights36.com/html/files/Pictures/Temp/ServiceManual.pdf
 

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Discussion Starter #5
Reviewing the data for the McCruise, they make three connections (plus power and ground): 1) ignition coil for tach pulse; 2) rear brake light switch; 3) speed sensor on top of the transmission. So I'm still wondering what is causing the transmission to go into safe mode.
 

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I would try disconnecting that tap on the speed sensor and see if it changes anything.
 

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Discussion Starter #7
Two votes for "disconnect the speed sensor tap".

Looking in the manual, there are four conditions listed that match my symptom, "Gearshift function does not work (while driving) - only shifted into first gear":

DTC 21-1 (or -2) Shift spindle angle sensor low (or high) voltage - faulty PCM ($$$)
DTC 22-1 (or 23-1) Shift spindle operation malfunction after (or during) operating gear shift mechanism - Gear shift mechanism malfunction and/or shift spindle angle sensor malfunction

I note none of these are touched by the cruise control.

I do not have access to an MCS - the manual allows for partial diagnostic capability lacking an MCS, though it is a little involved, to wit:

(12-9) 1. Turn the ignition switch OFF. Remove the seat.
2. Remove the DLC from the battery box (photo). Remove the dummy connector from the DLC. Short the terminals using a special tool. Connection: Brown - Green
[SCS service connector 070PZ-PY30100]
3. Make sure the engine stop switch is turned to [symbol for 'go']. While pushing the shift switch '+', turn the ignition switch ON. Read, and note the shift indicator "--" blinks, and refer to the trouble shooting index (page 12-11).
NOTE: If the PCM has no DTC in its memory, the shift indicator "--" will start blinking (page 12-10).
4. Release the shift switch "+"
 

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I bet the speed sensor. It is possible that the internal resistance of the cruise control is too low resulting a bad speed signal (pulses) to ECU. Somehow the pulse form can be deformed by the cruise control. If so, it would be impossible to find cure.
 

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Discussion Starter #9
I appreciate the logic. Have you worked with McCruise at all ?

This connection to the input for the speedometer (which is working fine, by the way) is part of the McCruise design - two brothers who spent years in the aerospace industry - a legacy reflected in the choice of components, the crimp of the wires, the exquisite instruction manuals.

In the case of the VS sensor (and the others), they simply do not use standard taps that break insulation and so on. In all cases, they provide either a piggy back connector or an inline (as with the speed sensor) insert.

I read back on this site to some early installers who report a similar problem, so you may well be right.

But simply disconnecting it is undesirable in the end, though it may well be a valid troubleshooting step.
 

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I appreciate the logic. Have you worked with McCruise at all ?

This connection to the input for the speedometer (which is working fine, by the way) is part of the McCruise design - two brothers who spent years in the aerospace industry - a legacy reflected in the choice of components, the crimp of the wires, the exquisite instruction manuals.

In the case of the VS sensor (and the others), they simply do not use standard taps that break insulation and so on. In all cases, they provide either a piggy back connector or an inline (as with the speed sensor) insert.

I read back on this site to some early installers who report a similar problem, so you may well be right.

But simply disconnecting it is undesirable in the end, though it may well be a valid troubleshooting step.
Of couse I was only guessing. Anyway if your bike is DCT it makes gear shifts based on the speed ( and other factors), not exactly on what the speedometer shows. There must be a connection between ECU and the speed sensor. I tried to use such a poor logic as if the bike worked fine before the cruise control was installed, the reason has to be the cruise control :).
 

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Discussion Starter #11
I would say EXCELLENT logic, and greatly appreciate your willingness to engage. It is clearly a primary consideration.

Now I have to face the heat, and pulling off all the plastic again to get to the connection - practice, practice, practice, they say, and wondering why, I can only look in a mirror.

THANK YOU !
 

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Im curious how you made the connection to the speed sensor.

I made a living out of fixing cars by looking at the service record to see who "fixed" it previously.

Make sure and let us know what you find.
 

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Discussion Starter #13
Make sure and let us know what you find.
I'm a huge believer in sharing what is found, in the hopes that others benefit.

I just looked, hopefully, at a long thread from 2018 with a similar problem, and was frustrated when the OP gave up and traded the bike in and no real resolution.

At the risk of adding nothing, the circumstantial information is strongly suggestive.

I remember a comparative culture class long ago, where it was said among a certain group of aboriginals, there was a belief that fertility depended on water from a certain stream. Of course, humans, up until the last century, lived on the edge of starvation, and just as a queen honey bee stops laying eggs in the fall as the availability of nectar dries up, it was reasonable to assume that when a woman was sated, that including drinking from a most limited resource, this was responsible for new life.

As facts were presented -- bike working fine -- deconstruct bike to install McCruise -- bike no longer working fine -- of the three connections presented (coil, brake switch, and speedometer input); the latter would be the most likely.

All that said, I am intrigued by the "shifter pin" reference, and the shifter motor, which, I will test before ordering one.

And as stated above, the manual lists four conditions that match my situation, of being able to shift to first, but being unable to shift while driving, and those four all have to do with erroneous data fed the PCM by the shift spindle angle sensor (did I somehow manage to disturb that while pulling and tugging on other wires ???).

This is turning into a scavenger hunt, and oh how I would like a "House" or "Sherlock" - @dgall ?

Be well.
 

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I’m still not sure exactly what the bike is doing. You start the bike in neutral with the N light on the dash. You push the mode button and you get the clunk into first gear in D mode, roll on the throttle and the bike moves forward all the way to where it should shift into second but it does not shift correct? As if it was in manual mode? If you try to use the shift buttons you get no response? Have you tried S mode and manual shifting then manual mode using the shift buttons?
I think its something to do with the cruise installation. I would call or email McCruise and see what they think first. I would pull the fuse on the cruise and see what happens. I would check all of the fuses in the fuse box. Tleventry blew the # 6 7.5A ILLUMI/STOP/ HORN) fuse and the bike would not shift out of 1st gear. A funny thing happened on the way to work....
Whoda thought blowing that fuse would affect the DCT in such a way. I would invest in the service connector and check for trouble codes.
 

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Discussion Starter #15 (Edited)
Thank you !

And funny (not haha - more amazing good) you mention the illum/stop/horn -- I had the EXACT same thing happen a while back - piss poor wiring job for the lights on the BESTEM top box some years ago -- went over a rough railroad crossing and the wires pulled from one of the connectors, and shorted.

I did send an email into McCruise - and the knee-jerk reaction - not unexpected - was "I have heard of that before. I would suspect a bad battery, and nothing to do with the cruise control !"

Correct:

--> Normal:

Turn on ignition with key

Side stand up

Stop switch ON [green 'N' and oil light are on]

Start engine

Ensure safe to go

Click "D", hear cluck and gear indicator shows "1"

Roll on throttle, bike moves forward

--> NOT normal

Gear indicator "1" disappears, replaced by "--"

Transmission will not respond to manual attempt to shift.

Shift indicator does respond to "S" and "D" change on the display - no indication of any change in the DCT

If going down hill and coasting, DCT disengages - effectively in neutral (though no "N" indicator)

Rolling to a stop, hear a clunk - and while no indication on the dash, the DCT has shifted into 2nd.

Turn off the bike.

Turn it back on, and turn ON the stop switch, hear the clunking of the DCT trying to return to neutral - the display shows "2".

Rock the bike slightly, and quickly, the green "N" alights.

Rinse and repeat.

Thank you !
 

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Discussion Starter #20
Took the bike out - per usual, started - it was in neutral - pushed "D" and that registered on the display.

Selected "M" and the "D" on the display disappeared.

As soon as I started rolling, however; the "1" gear indicator became "--" and no response to any DCT function.

When I rolled to a stop [this is the other peculiar aspect of this anomalous behavior] it clunks, shifting to 2nd.

Turn the bike off, and back on, in the DCT returns to neutral.
 
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