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Discussion Starter #1
My bike is an '05 Daytona 955i.
Problem is that (intermittently) the starter button won't crank the engine until the fuel pump prime is finished. I'm used to being able to turn on the ignition, see the instruments light up, and immediately start the engine.
Mostly for the last few rides the instruments are lit, the fuel pump runs but all that happens when I hit the starter (with clutch in) is that the headlamp cutout relay opens (lights go out) and the speed of the fuel pump decreases. It always cranks fine after the pump stops.

This happens with the bike in gear or neutral, with the stand up or down, but it's intermittent. Diagram on page 16.25 of the Triumph manual shows that the MC1000 ECU pin 2E1 supplies 12V for the fuel pump, headlight cutout relay coil, instruments and starter solenoid. It's as if the ECU cannot supply enough current to run the fuel pump and pull in the starter solenoid at the same time.

Has anyone seen this in a Daytona or Speed triple 955i?
IanB
 

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...Diagram on page 16.25 of the Triumph manual shows that the MC1000 ECU pin 2E1 supplies 12V for the fuel pump, headlight cutout relay coil, instruments and starter solenoid. It's as if the ECU cannot supply enough current to run the fuel pump and pull in the starter solenoid at the same time.
2/E1 is not a supply, it is an input.
The current source that powers that node comes from Fuse 5 via the ignition relay.
It is effectively the same source that goes via the Start switch to the starter relay.
Since the lights go out, then the starter relay itself is switching which means the positive side of the solenoid is most likely being powered (although you could try replacing the starter/headlight relay to be sure that as well as 'breaking' from the normally closed position, it indeed properly 'makes' to the normally open position which powers the solenoid)
the thing that differentiates the starter relay operating but not the solenoid is the clutch switch.
So I would look more to that as being the culprit.
 

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Discussion Starter #3
Thanks DeCosse. I missed where the 12V was coming from, through the ignition relay. It's called "alarm control unit" on page 1.64, but "ignition relay" in the main schematic, and also in the Haynes manual.
The starter solenoid doesn't depend on the headlamp cutout relay. The solenoid and relay coil are powered directly from the starter button, the N/O contact on the relay is not used. The relay contacts are in the ground return for the lights, not 12V.
I neglected to mention that when I press the starter with the clutch pulled in, if it doesn't crank immediately, and I keep the starter pressed, it always cranks after a second or two when the fuel pump stops. I think that exonerates the clutch switch.
Which leaves the ignition relay contacts. There is no alarm installed. It looks as if there is enough resistance there to prevent the solenoid working at the same time as the fuel pump. That would explain why I hear the pump slow down when I hit the starter, at a time when it doesn't crank immediately. I had thought this issue wasn't very important, but if the ignition relay contacts fail completely the bike won't go. I'll look at it tonight.
IanB
 

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...I missed where the 12V was coming from, through the ignition relay. It's called "alarm control unit" on page 1.64, but "ignition relay" in the main schematic, and also in the Haynes manual.
The alarm control and the ignition relay are separate things; the part you are missing that is not directly shown in the schematic is that 1 & 2 are jumpered as are 3 & 5 by either an actual alarm (unless immobilized) or by the alarm bypass connector
So effectively 1,2,3,4 &5 are ALL connected together.
The Ignition Relay (67) feeds pin 2 of the Alarm Connector (50) and is bridged to pin 1 which then feeds the ignition node

.... The starter solenoid doesn't depend on the headlamp cutout relay. The solenoid and relay coil are powered directly from the starter button, the N/O contact on the relay is not used. The relay contacts are in the ground return for the lights, not 12V.
You are correct of course, I was thinking out loud without looking directly at the schematic (that's how it works with 1050's & R3) - sometimes familiarity breeds contempt as they say and I failed to validate with the actual schematic in this case.
Yes, the Headlight Relay and the Solenoid coils are indeed in parallel (on the positive side) but again the differentiator with one working vs the other is the clutch switch on the ground side of the solenoid.
What we do know is that positive voltage is commonly applied to the solenoid and the headlight relay - the relay throws but the solenoid does not.
If there was insufficient current to throw the solenoid the common voltage across that node to all three of those devices would be affected alike and the voltage would sag accordingly
It's not like the node can selectively choose and say "well I'll send all my available current to the pump and the headlight relay, and the solenoid will just have to wait.

I neglected to mention that when I press the starter with the clutch pulled in, if it doesn't crank immediately, and I keep the starter pressed, it always cranks after a second or two when the fuel pump stops. I think that exonerates the clutch switch.
I think it's possibly coincidence and wouldn't say it's safe to 'exonerate' it.
The simple thing to do is just ground the negative side of the solenoid directly to the battery negative; then if you still have the problem you can indeed rule out the switch.
I would still say more likely problem on the negative than the positive side.

Along the lines of your original premise however, the other thing to look at might be the start switch itself - the current out of that only feeds both the solenoid and headlight relay - poor conductivity through that could result in a lower voltage (especially when pump is running) and that could be enough to cause the issue.
That whole ignition circuit is quite 'lossy' with relatively small gauge wires which have to provide a fairly high current simultaneously to the pump and solenoid, so you're looking at about 8A there in all. Voltage drop is directly proportional to current, so any high resistance junction in the circuit path could possibly cause enough drop to not allow the solenoid to throw.
The most likely place in that would be the start switch (which only affects the solenoid and relay) whose drop would be cumulative with that of the ignition relay (or interconnect wiring)
You will definitely see SOME voltage drop between the battery and the solenoid even if things are all 'normal' (to the limits of the OEM wiring) - but if any part of the series chain is unusually high resistance then accumulatively the last part of the chain would be affected most.

You should measure the voltage along the circuit path to see where the most loss is going on - one good node point is at any of pins 1,2,3,4 or 5 at the alarm bypass connector - easy to get to; measure voltage with respect to ground
Compare
1. With ignition on while pump is running (starter not attempted to operate just yet)
2. With ignition on after the pump has timed out
3. While the pump is running AND You have the starter/clutch buttons pressed

You should also measure the voltage at the solenoid
a. Solenoid negative to battery negative (this should be zero )
b. Solenoid positive to battery negative - compare this voltage to '3' above.

Again note, because you are potentially dealing with voltage drop issues, it is imperative that you capture each of these voltages when the load is actually in play i.e. while the pump is running AND the starter is demanded.
 

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Discussion Starter #5 (Edited)
the part you are missing that is not directly shown in the schematic is that 1 & 2 are jumpered as are 3 & 5 by either an actual alarm (unless immobilized) or by the alarm bypass connector
In the diagram on p16.25 of the Triumph manual, pins 1-5 of the alarm connector are shown connected to a 2 pole relay, called "Alarm Control Unit (accessory)". One pole connects pin 1 to pin 2, the other pin 3 to pin 5. The main schematic, and also the one in the Haynes manual show only the alarm connector, no relay or jumpers, as you said.
I knew my bike had the jumpers but I misinterpreted the source of 12V to the node as the ECU, not the ignition relay.

What we do know is that positive voltage is commonly applied to the solenoid and the headlight relay - the relay throws but the solenoid does not.
If there was insufficient current to throw the solenoid the common voltage across that node to all three of those devices would be affected alike and the voltage would sag accordingly
It's not like the node can selectively choose and say "well I'll send all my available current to the pump and the headlight relay, and the solenoid will just have to wait.
Of course I'm not suggesting that the node selectively distributes current. I think when I press the starter, the circuit from the node through the solenoid and clutch switch to ground is completed, some current flows through the solenoid coil, but due to resistance between the current source and the node the additional current causes the voltage at the node to sag (as you said). So there isn't enough voltage (and current) to pull the solenoid, and also the fuel pump slows down, as I hear. There is still enough voltage to transfer the headlamp cutout relay.

So, in the garage, I measured across the battery terminals, 12.35V.
At the alarm connector the static voltage (ignition on, pump stopped) was mostly 11.3V, but varied down to about 9V between successive cycles of the ignition switch.
With the pump priming, starter not pressed, mostly it was 9.8V.
Other times, with the engine cranking (in gear, stand down to prevent the engine starting) I saw mostly 9.5V.
Engine cranking while the pump was priming (no bug) 8.3V, but it dipped lower for an instant as the solenoid threw.
Battery voltage while cranking was 10.6V.
As I said, the issue is intermittent, but I caught the failure just once and saw <6V at the connector while the pump was priming with the starter pressed but no cranking.

Overall, there is at least 1.0V drop between the battery and the node. When the pump is priming it's 2.5V. Pump priming and cranking 2.3V. Not sure why it's less, but the drop increased momentarily at the instant the solenoid threw.

I think all these voltage drops are excessive, even though the wiring is lossy. Still suspecting the ignition relay, I swapped it with the one in my spare bike. The voltage drops still look high, but I never saw less than 8V on the node, even at the instant the solenoid was throwing, and I could not induce the failure to crank. I'll see how it goes on my next ride on Sunday.

IanB
 

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Discussion Starter #6
360km ride, all good so far since the ignition relay swap. Only about 10 starts today, but the delayed cranking was happening about half the time on the last couple of rides.
 

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Discussion Starter #7
After 3 months off the road following a crash the cranking delay was back. I didn't realise at the time, and became used to it. It has been there for 9 months continuously, not cranking until the fuel pump stops, even if you hold the starter button pressed. Yesterday I investigated, and fished out the alarm relay connector with the jumper plug. The voltage at the battery was 12.3V, at the jumper plug pin 5 it was 11.3V. The engine cranked immediately! Voltage while cranking was 10.3V.
Now it cranks immediately after the ignition is switched on or the kill switch is enabled, as it should.
I cannot make it fail now by moving the connector or jumper plug. No visible problem with the pins or wiring to the plug. Wait and see.
IanB
 

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I'm glad you wrote this because it jumped the thread up and I've been trying to diagnose a fail to crank situation. So the posts you and decosse made helped me to trace things through. Result: just came in from my garage having heard some cranking again!

I found the wiring loom so confusing, I drew my own diagram of the wires, relays and switches in the starter circuit. I did voltage readings all the way and saw very small voltage drops at each point. Until I got to the white/red at the starter solenoid where it was zero. The reading at the starter switch in the right hand handlebar cluster was very good. I had continuity from the starter switch to the block connector (right hand side of cockpit fairing). No continuity from that block connector down to the solenoid. So that was where my problem was.

It turned out to be corrosion of the copper where it is crimped onto the female spade connector. It looked black and had gone so high resistance, nothing was happening. So I undid the solenoid wiring and fished it out to the left side of the frame for access. I released the spades from their plastic insulators. Then I used flux-cored solder to clean, reinforce and join the wires to their connectors, insulated with some tape and the plastic covers, and coated with Dow Corning electrical grease.

Finally, I checked for continuity and voltage to the side from the starter switch, the later being 12.03v on my multimeter. Great. I couldn't check voltage up at the clutch switch for want of enough hands. But the clutch switch was cleaned up and tested fine. And it cranked over again.

I told the opportunity to clean the contacts in the starter switch too. There was a black spot evident where the switch had been contacting. I dismantled the switch and took off the scorch with some light work with fine wet and dry. One of the contacts lifted out so I could do it on the bench. The other was awkward to get at. Then reassembled with a dab the good old DC4.

So the long and the short of it is, cleaning and insulating joints all the way could help you out too.

Cheers

LeT
 

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