Starting Dilemma Tied To The Starter Solenoid

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Firstly, based on many posts I have read regarding the Bonneville, the problem I am having is a perennial one that Triumph has never solved. I'm hoping to get the attention of Carl S and/or MacBandit:
  1. After about 7 years, I am having starting issues with my 2016 Bonneville T100 (only 3300 miles!). Even with a “good” battery (am now on my second new battery), the starting success is intermittent – mostly a fail: all I get are clicks at the starter solenoid.
  1. Right out of the box, the 2nd new battery I’ve obtained (180 cca) tested at 12.97V. When installed, it started my motorcycle right away. After running for a minute, I shut it down and after a few seconds, started again. I may have done the once more and then it began failing again: I only got clicks at the starter solenoid. I tried to start the motorcycle again several times thereafter and same result: click at the solenoid !! The battery voltage held to at least 12.6V, which was good. For the hell of it, I had it tested at AutoZone and – unsurprisingly - it came back totally healthy. Then I attached jumper cables from my pickup and the motorcycle started right up !! When the cables were disconnected, it again failed: clicks at the solenoid
Finally, I jumpered across the 2 solenoid posts and it started right up !!!

I’m now doubting that the issue has anything to do with the battery per se.

So my question is:

Is it usual that a 2016 Bonneville with only 3300 miles on it would have a starter solenoid go south ??? My diagnostics are pointing to a failed solenoid.
 
Sure it’s possible the solenoid is faulty. From what you describe and how you were able to start it, I would lean toward it being faulty. Since you’ve replaced batteries and all connections checked, I’d take it out and replace it at this point. I don’t know if it’s usual or not for it to fail, but there’s no way to predict if you get unlucky and a component fails that I know of. I’ve had vehicles were a solenoid fails and some with original ones still working after decades.
 
Actually the fault may be in the starter relay. If the solenoid works when you jump it, it should work via the normal start circuit. The only thing in the circuit that could prevent that would be a failure of the starter relay to pick up that puts battery voltage to the solenoid. The low power side of the relay is fed power from the starter button (rocker switch depending on model) that draws a solenoid up inside the relay to connect battery power to the starter solenoid terminal (usually only the + Post as the case is grounded). If the start button is getting power to the starter relay, the starter relay may not be connecting the battery to the starter.
 
Actually the fault may be in the starter relay. If the solenoid works when you jump it, it should work via the normal start circuit. The only thing in the circuit that could prevent that would be a failure of the starter relay to pick up that puts battery voltage to the solenoid. The low power side of the relay is fed power from the starter button (rocker switch depending on model) that draws a solenoid up inside the relay to connect battery power to the starter solenoid terminal (usually only the + Post as the case is grounded). If the start button is getting power to the starter relay, the starter relay may not be connecting the battery to the starter.
Agree, it’s really the only other component left. How would you test it? Meter? I’d be tempted to buy one along with the solenoid if they weren’t expensive and call it a day.
 
Usually the test involves sticking a new relay in and seeing if it works. If it doesn't fix the problem, the problem is elsewhere. That said, it's a cheap alternative to replacing the starter or the starter solenoid.
I have not looked into how the starter solenoid is hooked up on these motorcycles. If it’s like on a car shouldn’t be too hard to replace it and the relay. Of course don’t know their cost.
 
Thanks for all responses. To AtomSplitter, you mention the “starter relay”. I’m not sure where (exactly) that is located. I am attaching a pic of what’s under my LH cover. What I have labeled at the Headlight relay is per p.17.23 of the service manual. Other pictures I’ve seen posted on the Internet have this labeled as the Starter relay. ???

I am attaching a series of pictures that describe what I have done since my initial post. Slide 3 is telling; something about these results is wrong.

My understanding is that the (referring to my slides), when the start button is pressed, the circuit across terminals 3 & 4 should energize the coil within the solenoid to internally bridge across terminals 1 & 2, allowing the current from #1 to flow to #2 and on down to the starter. I’m not sure how the “starter relay” is involved and the service manual offers nothing.

Having made the onboard tests I have documented, the only thing left to do is to remove the solenoid, and on the bench energize it while checking continuity/resistance across the #1 & #2 terminals. If I get no continuity, I will know that the solenoid coil is bad. If it checks out, then it may be something else (e.g., the starter relay).

I will post back later.
 

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That headlight relay is what shuts the headlight off when you connect the battery to the starter during a start cycle. It can also energize the starter's solenoid. Here's what I could find on the web: The start relay can be incorporated into the solenoid since its a low amperage circuit. According to my wiring diagram the start relay is energized by the headlight cutout relay. If the headlight cutout relay is faulty it won't pickup the start relay.
1737214752314.png
 
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Yes AtomSplitter - as often happens, shortly after I made my last post, I stumbled onto this June 2018 post on TriumphRat:
https://www.other forum/threads/physical-location-of-starter-relay.928977/

Sage Forchetto explained exacty what you did:

“… there's [both] a starter relay and a starter solenoid. The starter relay temporarily diverts headlamp power to the operating coil of the starter solenoid when the start button is pressed, which incidentally turns the headlight off to help the battery cope with the huge starter motor current demand. Unlike the normal Bonnies, it's located under the tank, along the frame backbone - right hand side."

Thanks for posting that wiring diagram.
 
Yes AtomSplitter - as often happens, shortly after I made my last post, I stumbled onto this June 2018 post on TriumphRat:
https://www.other forum/threads/physical-location-of-starter-relay.928977/

Sage Forchetto explained exacty what you did:

“… there's [both] a starter relay and a starter solenoid. The starter relay temporarily diverts headlamp power to the operating coil of the starter solenoid when the start button is pressed, which incidentally turns the headlight off to help the battery cope with the huge starter motor current demand. Unlike the normal Bonnies, it's located under the tank, along the frame backbone - right hand side."

Thanks for posting that wiring diagram.
Your welcome, I have the book with diagrams but don't have the scanner.
 
While I have yet to complete my test with an isolated solenoid on the bench, I just had an epiphany !! For the longest time, in blog posts and elsewhere, I have seen reference to a “starter relay” and a “headlight relay” – 2 seemingly unrelated components. AtomSmasher’s diagram pose (above) but me onto this epiphany. It turns out that the so-called “starter relay” and the so-called “headlight relay” are one and the same !! Much of the confusion ascribes to the Triumph service manual, which I have complained about several times. On its p.17.23, the component (shown in my photo in post #9) is referred to as the “Headlight relay”. However, on the foldout electrical diagram (p.17.111), the component is referred to as a “Starter relay” !! I confirmed this by inspecting the 5 wires (their colors) that connect to it. AtomSmasher’s diagram rightly labels this component as “Headlight Cut-out Relay” (see pic), port 87 of which feeds the starter solenoid (labeled “Start Relay” in AtomSmasher’s diagram).

With this in mind, Forchetto’s comment (regarding the starter relay):

“Unlike the normal Bonnies, it's located under the tank, along the frame backbone - right hand side.” may have been referring to a different Triumph make/model.

In any case, a far better name for this component would be “Starter/Headlight relay” or simply “Headlight Cut-out relay”.

As a final point, consider this other part of Forchetto’s comment regarding this component:

“[The component] temporarily diverts headlamp power to the operating coil of the starter solenoid when the start button is pressed, which incidentally turns the headlight off to help the battery cope with the huge starter motor current demand.”

NOWHERE in the Triumph service manual or Owners Manual is this critical statement made – ANYWHERE !!


The above is unrelated to my starting problem but this was an opportune time to make it.
 

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Here’s the “bench test”:

I isolated the solenoid in a small bench vise. I energized the 2 spades:
12.9V to #3; battery ground to #4.

When the connection was made, the solenoid immediately clicked ONCE.

In that configuration:

• I measured continuity across #3 and #4.
• Resistance across #3 and #4 was 0.3Ω

I believe this indicates that the solenoid is okay. So I guess I now turn attention to the Starter/Headlight Cut-out relay.
 
It's my experience relays are notorious for going bad when you need them most, like to start your bike when you're in the exact middle of nowhere.

Also I was an atomsplitter, not an atomsmasher as the former generates useful heat, the latter makes subatomic bits and bobs flying hither and yon for no useful purpose other than proving it can be done.
 
Sorry I got your name wrong AtomSplitter. As I said before, this site doesn't alow editing (correcting) once a post is made. (HUGE FROWN) Other forums don't have this constraint ...

Your other point about fickle relays is well taken ...
 
It’s a common issue and I recently had to replace my headlight-starter relay. $15 and done. I did remove the cover of the new one and drilled a smallish hole for the insertion of an appropriately sized poker (like a golf tee) to close the connection in the relay should this happen while not at home in the comfort of my garage. Should the relay fail, all I need to do is insert my golf tee: The headlight will go out and the bike will start. Then I pull the tee and all is well. Better than having to carry a relay on board all the time just in case; you can stick a tee anywhere.
 
In the pictures taken under the side cover above, the relay for the headlight is what actuates the starter relay which is next to it. The starter relay can be identified by the large guage wire from the battery + terminal on one side and the same heavy guage wire from the relay to the starter motor terminal (the relay is identified as "starter solenoid" in the photo). When the start button on the handlebar is depressed it closes a normally open contact switch in the headlight relay that diverts power from the headlight to the starter relay low amp contact coil. That coil energizes and draws up a full current contact bar to connect the battery side lead to the starter side line. With this relay closed full battery power is applied to the starter motor from the battery's + terminal and to ground through the starter's motor case to complete the circuit. When the start pushbutton button is released the headlight relay opens (normally using a spring to switch contacts from start to headlight) connecting the battery to the headlight circuit and dropping the starter relay out (opened by spring pressure), disconnecting the starter motor to battery + terminal.

With this arrangement either relay under the left side cover could prevent starting so both must be checked. When the starter relay is tested a distinct click should be heard as the contact bar is drawn up to contact the battery to the starter. If the relay is closed and you check continuity between the two posts it should show 0 ohms, if the resistance is infinite the relay is bad. If the starter relay tests good then the headlight cut-out relay is the most likely culprit. If that tests good then start at the handlebar and check the switch block is making contact to energize the headlight relay. After that it's a witch hunt looking for loose or corroded connections.

Oh, and thanks for correcting my handle in your posts MoreCowbell.
 
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