M-Unit Install Instructions

[Thors]

Never got a chance to work on this over the weekend. I'll get back on it this week...

Dog died this morning on the way to work. At first I thought the "M" had let me down! Not at all - fuse was toast so I started poking around. Shorted the positive battery terminal to the main power connect and got a smokey wire. Friggin shorted from rubbing on the battery box. I was able to yank the ignition wire and starter wire out of the M so I jambed the ignition wire into the live side of the fuse plug and stuck the fuse in to hold it. Shorted the starer wire directly and she came back to life! Back home into the garage...drove the cage to work. :angry:

Lesson learned - don't rush to get things back together and leave loose wires rubbing around...

 

[Thors]

Well, I spent 20 mins with the bike during lunch. I'm not feeling very optimistic about the M-Unit right now...it's acting like it's toasty. When I power the unit via it's main feed all of the lights come on, which is possibly an indication of a short or over-voltage...but it should only do that once the key is on (or power is applied to the "lock" terminal). Not jumping to any conclusions until I bench test it.... Now I have to sit here at work and be useless...can't concentrate with my bike broken!

 

[Th3InfamousI]

Do you think a spike from the VR toasted her?

 

[Thors]

Nope. Been thinking about it. I believe I had a short which was confirmed when I shorted past the fuse. From there I disconnected as much as I could and hard wired the ignition, jumped the starter and drove a couple miles home. At that point, the battery was not connected to anything but ignition, however...and here's the kicker...the VR was still connected to the M and everything else. So, what's the signal from a VR look like without a battery to level it out? I'm dredding the fact that I may have toasted it by leaving it connected with just the VR. I'll know in a couple hours...

 

[DRBarnhart]

So, what's the signal from a VR look like without a battery to level it out?

It would be all over the place!!! The voltage/amperage would be maxed out plus the flucuations would be enough to kill a piece of sensitive electronic equipment...

Dennis

 

[Thors]

It would be all over the place!!! The voltage/amperage would be maxed out plus the flucuations would be enough to kill a piece of sensitive electronic equipment...

Dennis

My thoughts exactly. I have the day off - guess what I'll be doing... :up:

 

[Thors]

Unfortunately I must report I have a toasted M-Unit. The smoke I thought I saw come from a wire came from the M...and this was before I hot wired it back together to get home. There is a small indicator area with a message next to it: "If this area damaged your screwed". Sure enough there's a little melted spot in the middle and metal showing. Went through all the wiring and found no shorts and everything working as it should. Sooo...1 M-Unit down and no idea what killed it. I was accelerating at a normal pace just after turning. Right blinker may have still been on at the point it shut down. Nothing else going on...so WTF...

Not willing to miss another day of riding though. I took the hand control module from my old Wire-plus - the blinkers, brake and horn input/outputs still worked when I ripped it out. Ignition and running lights are all on the key now and the WP handles the blinker/brakes. The starter output on the WP was toast so I hooked the "Start" button to the horn input and a starter relay on the output. The relay controls both the comp releases and the starter solenoid so its a low draw. Presto change-o I'm riding again. Key turns the bike off and no high/low beam. I still have a latching relay I was using for that before but didn't feel like putting it in.

I'm going to contact Spiegler and/or Motogadget and see what they say. I still love the M-Unit and I've seen so few stories of failure I have to assume this was a fluke...or that I f'd something up myself.

 

[Thors]

Got back to working on the diagram. Can anyone confirm the stock ignition switch (key) that comes with the Dogs - is that switched to ground? Sure looks it in the diagram but I wanted to be sure.

 

[Red Setter]

M - unit

Just read your thread Thors.
I have my 04 Ridgeback in the shop with electrical problems. just ordered the M-unit yesterday.
Now I'm wondering if M is for MUG!!

 

[Jwooky]

Got back to working on the diagram. Can anyone confirm the stock ignition switch (key) that comes with the Dogs - is that switched to ground? Sure looks it in the diagram but I wanted to be sure.

Yes it's switched to ground.

 

[Thors]

Just read your thread Thors.
I have my 04 Ridgeback in the shop with electrical problems. just ordered the M-unit yesterday.
Now I'm wondering if M is for MUG!!

I spoke with a rep at Spiegler yesterday and my M goes out to them today. They will do a diagnostic and get back to me within 48 hours of recieving it. I'm not worried - the unit has a great following in other bike communities and reliability is very high. My bike is like an electrical "Bermuda Triangle" so I wouldn't put too much stock in my issue. We'll see how it goes...

 

[DRBarnhart]

My bike is like an electrical "Bermuda Triangle" so I wouldn't put too much stock in my issue.

Without going back over old threads I'm wondering if your VR has been the problem all along? First with the EHC then with the WP and now with the M-Unit.

The reason I say this is the popped circuit breaker. Why would that happen considering it's only there to protect the bike from the VR? If any of the loads from the M went nuts, according to the manual:

Currents in the range from 18-40V (e. g. in case of defective controller) will trigger the activation of the horn.

Did that happen? With the internal protection in the M it doesn't seem like it would have blown the breaker (certainly not a 40A!). As I'm sure you know, there's more about the safety functions of the M in 7.2 of the manual. And in 7.1:

The device is working in a voltage range between 4 to 25V direct current. Use in vehicles without battery is not possible.

makes me think more than ever the popped breaker is definitely what killed your M!

Anyway, just my :zz2cents:

Dennis

 

[Thors]

Hey DR,
The VR was replaced post EHC death. That EHC died because the former owner broke the negative terminal on the battery and then rode with the wire loose. Took about 5 mins to smoke the EHC...which is exactly what I would expect...lol.

The way I had it wired, the M was on the 40amp fuse and I'm pretty sure it blew the fuse. Small puff of smoke from the M and then lights out. My lights are on the key accessory position wire so that indicates the M went, then the fuse. As far as the horn goes...I don't have one at the moment so I don't know if the M was trying to sound it at any time. Wish I did...and if I get another M I'm putting the horn back in!

 

[DRBarnhart]

The way I had it wired, the M was on the 40amp fuse and I'm pretty sure it blew the fuse.

I'm not sure that's the case and here's why I say that.... How you wired it there is are two parallet power sources, the battery and the VR. If the M was drawing enough current to blow the 40A fuse to the battery it would have been drawing the same amount from the VR which would mean there was a draw from the M unit of over 80A! Why would that be? The only wires on the bike that could potentially carry that much current would be the starter or battery cables since any of the smaller gauge wires would burn almost instantly with that much of a load.

My lights are on the key accessory position wire so that indicates the M went, then the fuse.

I'm not following you here... the load is the M unit which includes the lights, true?

As far as the horn goes...I don't have one at the moment so I don't know if the M was trying to sound it at any time. Wish I did...and if I get another M I'm putting the horn back in!

Seems like that may be a good thing to do!

Still pondering...

Dennis

 

[Thors]

Ahhh Ok, I see what you're saying there on the fuse issue. Kinda kills my other theory. So far, I see no signs the VR is having any issues - but who knows what was happenening at that moment. Next task is to fuse the VR separate from the main feed. That way if the fuse blows the main feed will be isolated from the VR. I'm still left with the question - why did the M blow?? I really hope Spiegler can give me root cause but that's usually hard to do with a solid state gizmo that's been "potted"...we'll see.

What I was saying with the lights is they are all wired to the accesory position of the key. My running lights do not go through the M-unit. No good reason other than I forgot them when I was doing the initial wiring and didn't feel like redoing the splice for that circuit.

EDIT: I was looking through the M install and they do recommend putting the M and the VR on the non-battery side of the fuse. With DR's insight, I feel this is a bad way to do things. Fuse blows because somethings shorted and the VR keeps pumping current to the circuits = BAD.

 

[DRBarnhart]

EDIT: I was looking through the M install and they do recommend putting the M and the VR on the non-battery side of the fuse. With DR's insight, I feel this is a bad way to do things. Fuse blows because somethings shorted and the VR keeps pumping current to the circuits = BAD.

It seems motogadget is somewhat contradicting themselves on this for exactly the reason you're saying... They tell you that you need to have a fuse between the battery and the VR to protect things if the VR causes a short to ground but at the same time if a short did happen that blows the fuse you'd have a "shorted" VR still connected to the M unit. Then there's the statement that you can't use the M without a battery which is exactly what happens when the fuse blows. Things that make you go "Hmmm..."

I think where the problem lies is that the Dog doesn't have a "vehicle main fuse" like the manual talks about, the fuse is only for the VR. Anyway, I totally agree with your plan to have the VR and M fused individually with both connected to the battery.

I'll be waiting to hear if Spiegler comes up with anything...

Keep up the good work T!!!

Dennis

 

[Thors]

Updated the diagram and added some instructions. Feedback appreciated.

My M should get to Spiegler tomorrow so hopefully I'll have some answers (and maybe a new M!) shortly.

 

[DRBarnhart]

Updated the diagram and added some instructions. Feedback appreciated.

Looks good but I'd like to make one comment on what I'm seeing... Shouldn't you show a connection from the M-Unit mounting screws to the battery as stated in the manual?:

The m-Unit is connected to vehicle ground by the two mounting screws. Therefore one of the mounting screws must connected directly to battery minus terminal.​

And if you didn't connect yours to the battery could that have something to do with the problem?

Just a thought...

Dennis

 

[Thors]

Thanks for pointing that out...I should make a point to reference that as its very important. I mounted my M to the battery box and used a piece of 8g wire with ring terminal under one of the mounting bolts for ground. Solid ground for the M (and the battery box).

EDIT: Intructions updated! :2thumbs:

 

[Raywood]

Thanks for pointing that out...I should make a point to reference that as its very important. I mounted my M to the battery box and used a piece of 8g wire with ring terminal under one of the mounting bolts for ground. Solid ground for the M (and the battery box).

EDIT: Intructions updated! :2thumbs:

I had issues with grounding my PDM to the battery box. Remember it is rubber mounted. Once I took it to the frame I didn't have anymore problems.