Intermittent shut off...

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Don't know about the COP issue but you're grounding out somewhere..check all wires for exposure to frame
 
I have checked a bunch of wires for high resistances, but I do need to check the switch also. If I had a wire to ground, then I'd think I'd be blowing fuses. Maybe?

I'm curious to find out what other guys are measuring at their COP plugs. Anyone take any readings yet???

Vinnie
 
hey vin, very limited time, with a crappy voltmeter, but i have some results:

one wire, with key on and engine on or off reads 12.1v +/- .02

the othe reads 11.6 with 'engine on' and 0 with engine off.
 
Thanks for taking the time to do a voltage check. Now what you have is what I'm getting as far as power on both sides, and only one side goes to 0 when you shut off the engine stop switch.

I just got done doing a lot of other checking on my bike. This is what I'm getting:

All COP plugs unplugged. Key switch on. Tried engine stop switch on and off positions......

Cylinders number:
1: Black/White wire-12v with switch on or off...Other wire-11.63v switch on and about .1v with switch off

2: Black/White wire-12v with switch on or off...Other wire-11.61v switch on and about .1v with switch off

3: Black/White wire-12v with switch on or off...Other wire-10.35v switch on and about .1v with switch off (low voltage on TCI wire on this plug)

4: Black/White wire-12v with switch on or off...Other wire-11.63v switch on and about .1v with switch off

Now this is starting to make sense. The Black/White wire going to the COP's is always powered up with key on and bike not running. The other wire is the one that gets power from the TCI when the key is on and the engine stop switch is ON. With the switch off, the power is cut to the TCI, and no power is measure on this wire. The 'hot' Black/White wire does not go through the engine stop switch, hence the constant 12v as long as the key switch is turned on.

I'm now seeing that I have a connection issue of some sort with the #3 cylinders plug. That's the one that gives me a loss of over 1 volt compared to the other plugs,,, but only on the TCI side. The constant 12v side is fine. Now I have to find out if it's the problem is a connector, or the TCI itself.

I'm still curious to see what other guys are getting on various cylinders.
Vinnie
 
I'm now seeing that I have a connection issue with the #3 cylinders plug. That's the one that gives me a loss of over 1 volt compared to the other plugs,,, but only on the TCI side. Now I have to find out if it's the connector at the TCI or the TCI itself.

I'm still curious to see what other guys are getting on various cylinders.
Vinnie

You know, I'm still thinking that WHERE your flywheel is parked may affect the voltage you see on #3. Remember that the TCI will ground the coil connection in order to discharge the coil into the spark plug, so it could be that the pickup coil is at the point where it's just about to send the pulse to the TCI to ground #3, hence the reduced voltage.
Why don't you start your engine, then stop it, then try your measurements again and see if it's still the same?
 
Great idea. I'll do that tomorrow being that it's getting late here in Colorado. I also wonder if that's the wire that feeds the fuel pump relay.

I see in the newer set of schematics (the ones in full color) that only 1 output from the TCI feeds not only the coil, but also the fuel pump relay. Maybe that draws it down a bit? The schematics don't label the coils 1-4, so I don't know which one is the feed to the relay. But I could unplug the fuel pump relay to check it if starting the engine and then shutting it down gives me the same reading.

Vinnie
 
hey man. good info here, looks like we're getting somewhere. that was JUST #2 cylinder.

can test others tomorrow at some point. see what #3 is acting like as well.

have u thought about putting stock coils back on to see if it fixes it?
 
I really didn't think about the stock coils because what a bunch of work, geez. But I do want to get this problem solved.

I really do think it's due to a power thing. I mean it's funny how a new battery has mostly made this problem all but go away. The old battery was giving me the problem almost all the time when I went slow. But now, I'm only getting it once in a while.

Now that I have put the seperate hot and ground wires from the reg/rec, I want to ride the bike and see how often, if ever, the bike does this. Not the charging is at 14.2v just a tick over idle speed. If this cures it, then it may be an issue with the COP's using more power and draws down the TCI unit unless it's getting adequate voltage.

Can't wait to see what you guys are getting on all your cylinders as far as voltage at the COP plug.

Vinnie
 
cylinder 1:
wire 1: on - 12.1 off - 11.9
wire 2: on - 11.3 off - 0

cylinder 2:
wire 1: on - 11.8 off - 11.8
wire 2: on - 11.2 off - 0

cylinder 3:
wire 1: on - 11.7 off - 11.8
wire 2: on - 7.5 off - 0

cylinder 4:
wire 1: on - 11.7 off - 11.8
wire 2: on - 11.2 off - 0


cylinder 3 is definitely off. it was much colder this morning when i was doing it, bu tthe battery had been on the triclke charger all night. with key on or off I was getting about 12.5V across the terminals (thru the trickle charger pigtail)

but also, this is taking the COPs right out of the equation, its basically the same voltage you should get if u unplugged the coils from the stock setup eh? so not sure what this is proving, except that your #3 cylinder is acting the same way mine is.
 
This is getting interesting as hell. You have a lower voltage on cylinder 3 just like, and now I'm trying to find out why.

After looking at the full color schemetics, I was noticing that one of the outputs from the TCI not only feeds a coil, but also feeds the fuel pump relay. I'm wondering if that robs that one coil of a bit of voltage. On the schematics it doesn't say which coil it is specifically because it doesn't number them. But, it would be interesting to take the same readings on cylinders 1-4 with the fuel pump relay unplugged, and see what you get.

I may do this tonight. Would you also want to do this and see what you get?

Vinnie
 
OK here are my readings - all COPs disconnected, wire 1 is the black/white and wire 2 has a different color on each cylinder.

cylinder 1:
wire 1: on - 11.2 off - 11.4
wire 2: on - 10.74 off - 0.03

cylinder 2:
wire 1: on - 11.22 off - 11.39
wire 2: on - 9.68 off - 0.19

cylinder 3:
wire 1: on - 11.27 off - 11.39
wire 2: on - 10.8 off - 0.04

cylinder 4:
wire 1: on - 11.28 off - 11.38
wire 2: on - 10.82 off - 0.03

So I get a similar reading, only here it's #2 that's lower instead of you guy's #3.

Also, to verify my theory, I cranked the motor and took a second reading, and all were the same withing .2 volts of original figures.

Not quite sure why I'm still getting a really low voltage with the kill switch off:ummm:
 
I was just thinking a little more about this stuff. You're right, the COP's are out of the equation during this test. But, what about when the bike is running and all COP's are plugged in? Maybe the excess current draw from the low resistance of the COP's is causing such a voltage drop on the one cylinder, that it's feeling like the bike is shutting off?

Maybe it's just one cylinder, at low rpm where the bikes charging system is not at max, that intermittently drops out and makes the bike feel like it stuttered for a 1/2 second.

Just trying to think this through. If I find that the fuel pump relay is causing this issue, and it's because it robs a little current from just one output of the TCI unit, then maybe I'll try and find a way to feed the fuel pump relay from another source.

I gotta get some readings with the fuel pump relay unplugged to test this out.

Vinnie
 
What year bikes do you guys own? I'm wondering if there a difference with the old vs new TCI units.

I have a 2001 so it's the newer style TCI,,, 3JP-13. The bike originally came with a 3JP-12, but I sold that one when I got the Dyna 3000. When I blew that one up, I purchased a new one and it looks like they revised the part number for some reason.

Vinnie
 
yea NG has an older model, i'm running with a 2k3. that may equate for the difference in the cylinder readings? u and i getting 3, he's getting cyl#2 actin.
 
still kinda strange that just one cylinder would be getting less voltage. Maybe something to do with the Vboost controller, since it monitors #2 85-89 and #3 90-07?
 
On the full color schematics, do you know which coil is being referred to as far as being hooked to the fuel pump relay? I think they did the wiring this way because the TCI signal being fed to the coil, and tapped into by the fuel pump relay only lets the fuel pump continue to run when the bike is running. Otherwise you only get that 5 second pulse when you turn on the engine stop switch.

That's why I'm going to try and get readings with the fuel pump relay unplugged. I'll also look at the schematics and see how the VBoost is hooked up. Maybe I'll unplug that also and see what readings I get.

Vinnie
 
is the fuel pump relay just the plug right next to the #3 cyl that u unplug when doing carb work?

ng might be onto something with vboost.
 
The fuel pump relay is located under the left front air scoop. It's the first relay on the left side.

According to the schematics, the TCI has an attachment to one of the coils (don't know which one exactly) and also the tachometer. That's why I'm thinking that the relay is taking some power from the TCI and it only shows up on one coil plug.

Now, I just looked at those same schematics, and you guys are exactly right. The VBoost controller also has an attachment to the TCI and only 1 coil. So now I see that the fuel pump relay is on one TCI/coil connection and the fuel pump relay is on another TCI/coil connection.

Now I have 2 things to unplug to see which one may be drawing down the number 3 plug voltage reading.

Hmmm, gotta get to work on this and figure this out.
Vinnie
 
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