Electrical issue once more.......

britman

Nitrous
Joined
Sep 8, 2006
Messages
1,392
Location
Fredericksburg, Virginia
Ride
2005 Rocket 3/2014 Moto Guzzi Touring
Seems like about every couple of years my 05 Rocket has a slight electrical problem just to pee in my Cheerios. Maybe it is just seeking attention, jealous of the other "Girls" in the herd. (Since the Italian b*^%h arrived it seems to getting a little more frequent.) Here is the scenario, turn the key on, gauges sweep, headlights come on, horn and turn signals will work, but when you hit the starter button, nothing. Headlights do not cut out, and there is absolutely no response. During this problem the Gi-pro indicator blinks continually going between the gears. Usually turning the key back off and on again will rectify the problem, bike starts right up and Gi-Pro is fine. Bike has an Eastern Beaver headlight kit installed and on it's second ignition switch. I have checked the kick stand switch, it is fine. I have also replaced the headlight cut out relay with a new one, but the problem still shows up intermittently, and usually after the bike has been sitting for a period of time. Also battery is fairly new and kept on a trickle charger and tests great. Input from any of you electrical geniuses would greatly appreciated. I am leaning toward ignition switch again but thought I may be overlooking something.............
 
... turn the key on, gauges sweep, headlights come on, horn and turn signals will work, but when you hit the starter button, nothing. Headlights do not cut out, and there is absolutely no response. ... I am leaning toward ignition switch again but thought I may be overlooking something ......

It is unlikely the key-switch and especially since you have a headlight-current bypass in play - but also, since the headlights are on, that validates that current is at least flowing through the headlight/starter relay, so that circuit must be complete already.

The first clue is that 'nothing' happens when you press the start button - specifically, the headlights do not go off.
That means that the headlight relay is not changing state:
it requires two signals to enable that relay -
1) the positive signal from the start switch
2) the negative 'enable' signal from the ECU

The positive signal (White/Red wire) is fairly easy to check - measure for 12V with respect to battery negative with the ignition on and the button pressed.
I would suggest unlikely the problem is in the positive signal - the switch only has to supply about 140mA of current, so poor connection is unlikely from pitted contacts such as you might see in bikes which are directly switching the solenoid current (several amps in their case)
Then you have the negative signal, which originates from the ECU.
That signal is an interlock that depends on several inputs - the clutch switch being the most notable, but also the system voltage and the side-stand and neutral switches.
It always requires the clutch to be made and depending on the gear selection/neutral will also determine whether the side-stand is a factor.
Normally I would just point to the clutch switch as the most likely cause here - however the other behaviour (of GPI) would not be affected by that.

The second clue is the behaviour of the GPI - which do you have, the DS or the ATRE?
Regardless, this is going to also be related to the ECU
To where did you connect the Switched Power source for the GPI (whichever one you have)
If you connected to the Park Light circuit, then same status applies as per the headlights being on - that power sourced by same pole on key-switch.
Question - is the Neutral Light on (on the actual OEM instrument) ?
What happens with the GiPro if you select a gear?

Now - it COULD be a problem with the Ignition circuit itself - the fact that the gauges sweep I would tend to discount that - but you should validate that by measuring voltage (while in fault condition)
Check the voltage at Fuse # 5 with the key-switch on and the Run/Kill in the Run position
(set the black probe to the battery negative then leave the fuse in place and just touch the red probe to either of the metal tabs on the top of the fuse - voltage at both tabs indicates the fuse is intact)
The voltage should be approx same as at the battery positive (there may be a slight loss)
You can similarly measure the voltages at fuses 8 & 9, which will again validate or question the integrity of the key-switch circuits.

If that is all good my next suspicion would actually be the ECU Power Relay
As matter of course, you can try swapping this one with the Fan Relay position (at least for test) - don't swap with the pump relay just in case the ECU one is indeed the problem.

I would expect the ECU relay could account for both symptoms you are seeing
 
It is unlikely the key-switch and especially since you have a headlight-current bypass in play - but also, since the headlights are on, that validates that current is at least flowing through the headlight/starter relay, so that circuit must be complete already.

The first clue is that 'nothing' happens when you press the start button - specifically, the headlights do not go off.
That means that the headlight relay is not changing state:
it requires two signals to enable that relay -
1) the positive signal from the start switch
2) the negative 'enable' signal from the ECU

The positive signal (White/Red wire) is fairly easy to check - measure for 12V with respect to battery negative with the ignition on and the button pressed.
I would suggest unlikely the problem is in the positive signal - the switch only has to supply about 140mA of current, so poor connection is unlikely from pitted contacts such as you might see in bikes which are directly switching the solenoid current (several amps in their case)
Then you have the negative signal, which originates from the ECU.
That signal is an interlock that depends on several inputs - the clutch switch being the most notable, but also the system voltage and the side-stand and neutral switches.
It always requires the clutch to be made and depending on the gear selection/neutral will also determine whether the side-stand is a factor.
Normally I would just point to the clutch switch as the most likely cause here - however the other behaviour (of GPI) would not be affected by that.

The second clue is the behaviour of the GPI - which do you have, the DS or the ATRE?
Regardless, this is going to also be related to the ECU
To where did you connect the Switched Power source for the GPI (whichever one you have)
If you connected to the Park Light circuit, then same status applies as per the headlights being on - that power sourced by same pole on key-switch.
Question - is the Neutral Light on (on the actual OEM instrument) ?
What happens with the GiPro if you select a gear?

Now - it COULD be a problem with the Ignition circuit itself - the fact that the gauges sweep I would tend to discount that - but you should validate that by measuring voltage (while in fault condition)
Check the voltage at Fuse # 5 with the key-switch on and the Run/Kill in the Run position
(set the black probe to the battery negative then leave the fuse in place and just touch the red probe to either of the metal tabs on the top of the fuse - voltage at both tabs indicates the fuse is intact)
The voltage should be approx same as at the battery positive (there may be a slight loss)
You can similarly measure the voltages at fuses 8 & 9, which will again validate or question the integrity of the key-switch circuits.

If that is all good my next suspicion would actually be the ECU Power Relay
As matter of course, you can try swapping this one with the Fan Relay position (at least for test) - don't swap with the pump relay just in case the ECU one is indeed the problem.

I would expect the ECU relay could account for both symptoms you are seeing
That's a fantastic reply Ken - You never let us down with your replies. You are a great asset to this forum mate.
Thank You.
 
DEcosse,

I bow to your knowledge sir. I will go through your check list this weekend and if I recall I have the ATRE version of the GiPro. I still have the paperwork in my files and will verify the point of hookup also. Hopefully I can get the bike to malfunction again and I will also check the gear selection aspect, but I do know the OEM neutral light is on when it happens. Thanks again for your help and all of the input you provide to others on this site when the positive and negative electrical gremlins appear.......
 
Bike bandit shows these relays in a set of 3, if it is failure of the ECU Power Relay would it be wise to replace all three, or just the suspected culprit. Is Triumph (OEM)the only source or are there any crossover universal models out there. Again input is really appreciated from someone who still knows how install a set of points, but at a loss as what a relay really does to earn its keep.....
 
DEcosse, I bow to your knowledge sir. I will go through your check list this weekend and if I recall I have the ATRE version of the GiPro. I still have the paperwork in my files and will verify the point of hookup also. Hopefully I can get the bike to malfunction again and I will also check the gear selection aspect, but I do know the OEM neutral light is on when it happens. Thanks again for your help and all of the input you provide to others on this site when the positive and negative electrical gremlins appear.......
If you have the ATRE version there is a way to nullify its' influence on the GEAR POSITION SIGNAL from the GEAR POSITION SENSOR. Basically you connect the input and output signal wires from the GiPro and "tap" into the OEM wire. All it does then is work as a gear indicator. This info came fro the mfr HealTech though they do not recommend it.

The normal and Change over relays are pretty commonplace - general automotive relays. My advice though is buy GOOD ONES. Some of the much cheaper ones from China CAN be less than cooperative. Ken (I'm sure) can probably even point you at Solid State relays ;) - In the US I can't really advise where to source - sorry.
 
Hate to be contrary here but I would actually I would recommend to stick with OEM here - they have a special suppression scheme specifically for application for being driven by ECU;
You can see the configuration directly on the side of the relay - it has a parallel resistor across the coil and a blocking diode in series with it.
(the 85 terminal is directly connected to the ECU driver)

When relays turn off they generate a HUGE voltage spike which can easily be several hundred volts (this is exactly how an ignition coil works);
the resistor helps to limit the voltage and quickly dissipate the current generated by the collapsing field of the relay coil;
the diode allows it to turn on for its normal operation but blocks the negative voltage of the spike, during turn-off, regardless of its magnitude.

Is it overkill? Maybe .......... but personally I would give the ECU the maximum protection affordable.

It's not really difficult - or expensive - to modify a common or garden automotive relay to similar config for much lower cost;
but for most it's not worth the hassle.

Solid-state relay definitely eliminates any danger of high voltage spikes, but they are expensive and there are not readily available in an automotive mini-relay format
(BEWARE of products like this one .............. HELLA 931680011 12V 20/40 Amp SPDT RES Solid-State Relay NEW FREE SHIPPING | eBay
Refer to the manufacturer spec - it is simply a resistor suppressed common coil operated relay)

I would not personally replace all three 'just because' but that would be a personal choice in which I would not see major fault in an argument to do so.
But also note I'm speculating a bit here, it may not necessarily be the problem and just swapping them around may prove/disprove that suggestion before you invest any money in them.

OEM Relay for ECU connection
 
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I would like to thank DEcosse for all the time he has taken to help all of us out on this rocket site. He has gave us great information and has been very patient with us and gave us long typed out paragraphs to help us understand the rocket. thanks
i would like to add a little to the great info DEcosse gave. i assume that u must be a good mechanic by the look of your tool box and MC's.
if i were work on this bike i would first check fuses and power(like said). then i would pull the right side cover i would make sure it was in neutral disengage the clutch lever (large rubber band or plastic tie) turn on ign turn on turn signal. there r two relays u should be able to fell the one clicking the other will be the starter relay. turn off turn signals then press the starter button if u can fell the relay click then the system that works to energize the relay is ok . if it does not start u can check the 12 volts from fuse 9.
if it does not click the problem most likely could be starter button, clutch lever switch. a lot of what i saying has been said i just use the clicking as a tool. if u need to get technical u can make 5 jumper wires in between the connector an relay so u can check voltage.
i bought a starter relay (aka change over relay) about three years ago $10.95 list $14.99 #T2501705 that i just keep for a spare. i think that it would work to replace the other relays.
well my finger is wore out and i do not do weekends. hth
 
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