2007 MTX Phazer D & R lights

[Dave Macpherson]

2007 MTX Phazer
D & R Lights are not illuminated
Pressing Reverse Button has no effect
Engine will only rev to 3000
Starts right up
Have verified connectivity in the wire harness
Have confirmed Neutral Switches work, Drive is grounded, Reverse is open.
Have tried switching ECU, no change
No codes or check engine light are active
The meter seems to work otherwise, I can get codes & other lights work.

Has anyone encountered this? I cannot find a reference online or in the manual to a similar symptom.

Any help is appreciated,

Dave

 

[Mooseman]

If it's limiting RPM, it thinks it's either in R or it doesn't know what it's in.

Have you Tried starting it by turning the key straight to crank? This is a bypass mode to get it to shift. I used to do this when it would do nothing when pushing the button and I had to shut down and restart. However mine did have the D light on but it did sometimes flash while riding, especially when decelerating, which I think is the reason why it would not want to shift after riding a while. Never was able to fix it.

Have confirmed Neutral Switches work,

What are the Neutral Switches? If you mean the D and R grounding switches, they ground just from contact with the internal shift fork.

Try grounding the R wire and see what happens. So you checked both wires' continuity to the ECU? Checked the fuse and relays? Looking at the schematics, there are only two wires coming from the ECU that control the relays that make the shift motor move; Sb/W (sky blue/white) and Br/B (brown/black) where the ECU would ground one or the other. With the key off, I would put 12v+ to the shift motor fuse (pull the fuse to not backfeed) and 12v- to the Sb/W and then to Br/B to see if the shift motor works.

It's a very finicky and troublesome system. If I would have delved into it more when I had it, I would have permanently grounded the D wire, disconnected the R wire and put my own SPDT switch to ground the relay wires manually, bypassing the ECU.

 

[Dave Macpherson]

If it's limiting RPM, it thinks it's either in R or it doesn't know what it's in.

Have you Tried starting it by turning the key straight to crank? This is a bypass mode to get it to shift. I used to do this when it would do nothing when pushing the button and I had to shut down and restart. However mine did have the D light on but it did sometimes flash while riding, especially when decelerating, which I think is the reason why it would not want to shift after riding a while. Never was able to fix it.


What are the Neutral Switches? If you mean the D and R grounding switches, they ground just from contact with the internal shift fork.

Try grounding the R wire and see what happens. So you checked both wires' continuity to the ECU? Checked the fuse and relays? Looking at the schematics, there are only two wires coming from the ECU that control the relays that make the shift motor move; Sb/W (sky blue/white) and Br/B (brown/black) where the ECU would ground one or the other. With the key off, I would put 12v+ to the shift motor fuse (pull the fuse to not backfeed) and 12v- to the Sb/W and then to Br/B to see if the shift motor works.

It's a very finicky and troublesome system. If I would have delved into it more when I had it, I would have permanently grounded the D wire, disconnected the R wire and put my own SPDT switch to ground the relay wires manually, bypassing the ECU.

Thank you for the thoughtful reply,

I was not aware of the straight to crank bypass mode, ill try that and report back.

Yes, my reference to the neutral switches is the D & R ground switches, they are open when not in contact with the fork and grounded when in drive or reverse. I have tried a jumper from the wire to ground on both sides and the speedometer dose not respond.

The shift motor does work, following the directions in the manual I have been able to get it to cycle between forward and reverse and can confirm both the mechanical system function by rotating the secondary clutch and the switches work by checking with a multimeter.

I have verified all the wires between the ECU & speedometer are intact & done the same for the D & R switch wires. I have checked all fuses & relays.

At this point I think trying a different speedometer is the way to go, I'm trying to source one for a reasonable price & will report back when I complete that step.

*I have never had this machine working, it was purchased as a Basket Case & I am enjoying the process of troubleshooting the systems, these forums have been very helpful & I have spent much time reading Mooseman posts!*

 

[Mooseman]

*I have never had this machine working, it was purchased as a Basket Case & I am enjoying the process of troubleshooting the systems, these forums have been very helpful & I have spent much time reading Mooseman posts!*

Don't you just love those! I did some work for a guy who bought one not knowing what to look for. It had almost all the problems that *we* know about. Mostly mechanical issues. Took 57 hours of work to get it to a rideable condition. The only issue he has left is long cranking times because he doesn't have the cold start updated ECU.

Looked again at the schematics and I can't even see the shift button or can differentiate a wire that would work the D and R LEDs. I'm think one or both wires that go to the ECU are communication type, like a CANBUS in a car system. It could very well be the speedo that's borked where some functions are dead but not others. I hate just shotgunning parts at a problem but at this point, there's not much else.

 

[Dave Macpherson]

I have no had success sourcing a speedometer, thought i had one but its worse.

Straight to crank produces no change in symptom.

I checked the coil resistance and found them within spec.

Next things I can think of are to look into ignition timing and crank position sensor.

It seems like the TORS system is activating but i have it in bypass & there is no code. It makes sense that it would block an RMP increase without confirming the drive is engaged so i would like to rule that out, need to see the green light.

I'm also wondering about throttle position sensor, it seems fine in Diagnostic Mode, increases smoothly from 18-100, but I have not tested it following the resistance measurement procedure in the Service Manual.

I will post updates as i work through this

 

[Mooseman]

It doesn't sound like TORS without the light and a code. Sounds more like the RPM restriction from the shifting system. I think I've had an occasion or two where the neither light was on and the sled wouldn't move same as yours. After futzing with it a bit, the D light would come on and then would move and shift.

Here's another one you can try, unplug both the D and R grounding switches from the gear box and unplug the ECU, check for a short between the two and each to ground. There should be nothing. Reconnect everything, back probe each wire and check again. Only the D wire should be grounded.

 

[Dave Macpherson]

I checked the wires for faults following the process described above, all good.

While doing that I noticed the drive and reverse signal wires were reversed, such that WL was on R and WR on D. Silly to not have noticed that sooner, i corrected them.

At the same time i looked at the Throttle Position Sensor. I found it to work correctly in Diagnostic mode but when connected to a multimeter it seems to loose continuity when not moving. Resistance increases to the specification but if holding still at an angle other than closed the circuit reads open. I gave it a good rinse with contact cleaner and blew it out with compressed air a few times and it seems better.

The RPMs increase normally but I still have no green light. Certainly a step in the right direction. I have not tried driving it or switching to reverse, will provide an update when i get to that.

Thanks again for the help!

 

[Dave Macpherson]

I located a parts machine and have an update:

Tested the subject sled with the original dash(no green light) works fine on a stand. On the ground under load the transmission locked up almost immediately. I was able to get it to unlock be tunning the secondary back and forth a bit.

Scavenged the display from my parts machine and I now have a green light. I rode around for about 20min with no trouble, went down up and down some steep hills, did some hard accelerating and engine braking. Solid green light no popping out of gear.

The only persistent issue is reverse is not available. Pressing the button has no effect, light remains green, no noise from the actuator.

I am going to take the shrouds off tomorrow, check fluids and torques and look for the issue with reverse.

I will provide an update when I find the problem but until then I am happy with forward only.

 

[Mooseman]

The "push the button and nothing happens" is well documented here but no final fix has ever been found. However, turning the key directly to crank allows you to shift into reverse. When it would happen to me, I had to turn off the engine and restart directly to crank however it doesn't work for the next time during that same restart.