885i no cranking

[the slow heart]

Hi guys,
my ponnie refuses turn over so I rolled up my sleeves.

First out was the starter as long ago suspect for lazy starts - it was quite clean with perfect bearings which were regreased, no grooves on the copper contacts of the rotor, mildly worn brushes working at noticable spring contact. I tested it separately, it spins fine. Feed wire clean in good condition, wire ends clean and secure. The minus wires from the alternator also securely attached to the tranny casing.

Then I checked the starter relay - it clicks fast on direct 12v feed, the heavy contacts closure tested and found perfect. The black/pink wire brings the minus on it  readily on clutch activation. The white/red wire which should bring the plus from the starter button kind of does it not. When I attempt starting, the lights cut out relay clicks in with dash lights dim .... and that's it, starter relay does not click as it should.

The other regular old suspect, the battery, is an old one, maintained on a tender. I thought about insufficient voltage, and backed up the starting by car battery with same no success, might be the cables were not firmly attached.

Also neutral functions fine.
Also the side stand switch works fine when I tested it.

Anyway I am still testing and inspecting the starting wires, so any positive advice for tricky items involved is highly appreciated!

Regards,
K.

[the slow heart]

Walking down the plus cable of the starter relay, start button and engine stop switch proved to be ok, it was the ignition switch making poor contacts. Resoldered the pins and voala - bike is cranking as expected.

[HockleyBoy]

Excellent you got there, the ignition pins can be a problem on the later models as as well.

[the slow heart]

Had few tanks vaporized, and the problem showed up again 

New battery now, tracking wires again.
Where is the alarm connector located actually? Manual says some bikes are built without one and I suppose their wiring is a bit different from the one printed in the booklet where the connector is shown as item 74.

I suppose my bike has no such connector. But if there is such one, continuity between start button and starter relay might be degraded there.

[Lee337]

If an alarm is fitted (I'm not sure on the 855i) and it's anything like the late 955i, the alarm module is underneath the rear cowl. Had to remove the luggage rack to gain access.

Had my alarm go a couple of months ago so used a jumper to get the bike going again. The internal alarm battery eventually goes & once that happens, the immobiliser kicks in.

[the slow heart]

Thank you,

had the tail off for painting, but did not pay attention what was under,
will open that drawer again to invalidate one troubling option.

Meanwhile did some measurements to dream over:

- resistance between minus terminal of the battery and grounding wire terminal on alternator casing: 0.2 ohm

- resistance of starter relay coil: about 14 ohm

- new charged battery: 12.85 v

- current draw from battery with ignition on: 2.65 A, voltage drop 0.2 V

- current draw from battery with ignition on and engine stop on: dropping from 6.2 A initially to 4.1 A in few seconds, voltage drop 0.3 V initially to 0.2 V

-  resistance between minus terminal of the battery and minus connector of starter relay: 88 ohm clutch out, 0.1 clutch in

- voltage on plus connector of starter relay: 10 v before button push, 6.2 v after button push and clutch in ( battery goes down to 12.2 v while pushing the button )

Rough estimate to figure out the problem: at least couple beer cases, 12 pack 

[Sin_Tiger]

The T400 / T300 looms were all built with the wiring for the alarm integrated into the loom. There were a couple of variations up to 96 / post 96 where there were either two or three plugs, one of the plugs has a "dummy" plug with a bridging wire to allow use without an alarm being fitted. On the Steamers, the bridge / bypass is normally under the headlight cover. The 885i being in between could possibly be there.

Look for a plug that looks like the one below (ignore the longer wires), if the bypass plug and wires look OK, check the matching wires on the loom where they enter the matching plug. It's not an uncommon failure on the T300 models for them to break or corrode. If the plug is missing or the loom wires are damaged, it's often simpler just to bridge those two wires on the loom side rather than trying to repair them or find a plug.

[the slow heart]

Thanks guys,

there it was the alarm connector under the rear rack. It came quite clean, with protecting paste inside. Measured it and found no additional resistance, so left the plug and both bridges as they were.


Also measured resistance from the battery plus terminal to starter relay - 1.2 ohm. Seems negligable after 22 points of mechanical contact. But then I measured the starter relay coil resistance isolated, and found 4.1 ohm. Now I find them comparable. Meaning just 2.5 A current could reduce coil voltage under 10V which I actually measured. Will gaze bit more are the regular consumers in this condition qualifying for 30 W consumption or shall I look for loom leaks around them.

Kind of out of more ideas,
except cleaning and flushing switches and contacts as much as possible.

[the slow heart]

A friend of mine suspected the starter relay - what is the minimum voltage to activate a good one?

Since mine keeps silence on 10 V,
may it be faulty when clicking loudly on 12.5 V?

 

[Sin_Tiger]

   quite possibly. If you feel brave, jump the contacts of the relay with something metallic    Not so sure if the EFI will like less than 11v though.

[the slow heart]

Mistery revealed I think.

Isolated testing of the starter relay proved that it is activated even at quite lower voltage than the nominal - mine clicked at 6-7 volts and was holding the contact even at 5 volts. It was mistake to not test it this way initially, but I had no variable resistance at hand to play with the voltage, hence the sole measurement of its continuity. My false conclusion that it is not clicking at 10 volts didn't take into accaunt the poor connections ruining it.

So it turned out to be just connectors cleaning business. Since starting chain connections were bad it was reasonable to clean as much from the installation as possible, the rest will be winter job.

Both handlebar wiring connectors are the same type as the alarm connector, small cable terminals requiring great deal of patience and tools improvisation to clean. Ignition key connector was bigger and easier. So it was the fuse box. The consoles switches and buttons were really pain in the a** - full of small springs and rollers ready to fly over the garage floor on disassembly. The emergency lights switch won it hands down - micro spring inside small spring :) And why Triumph choose the springs in the buttons to serve as part of the electric chain? Instead one point of interruption we gain two more  potential problematic spots.

Also cleaned the headlights cut out relay chain, as a brunch of the starter chain and potential voltage sink in case of malfunction.

Finally, the resistance of the relay chain dropped from 2.1-2,2 ohms to 0.6-0,7 with voltage gain from 10 to 11.6-11.7 on the feed wire. On button push and starter cranking the engine, the new battery drops to 12.1- 12.2 volts on the terminals, relay feed voltage about 8,5 volts holding the contact ok and starter spinning at nominal pace.

As a precaution I rearranged the starter relay control wire connectors accessible after just seat removal. This way same sort of further mishap could be emergency cured by fast jump feed of both + and - cables.

[Sin_Tiger]

 

[the slow heart]

Some time passed since my last fight with the wiring looms of the bike.
And since I haven't done any more amends to the wiring diagram,
thought it is a good idea to post it here as a reference if someone needs it.

First it was a bit of distraction for me as non native English user
to think which color code corresponds to which wire color, so I added this info on top of the diagram.
Then added all the item names so no necessity to go looking on the page with the item numbers
( and forget the part of the wire labyrinth currently loaded in your short time memory ).
Then amended the fuse box legend listing all the items fed from particular fuse ( up to another fuse ).
Should be handy as fast starting point for isolating or tracing branches/ problems in the installation.
Ignition key internal wiring was not shown correctly, so I amended it.
Also added the missing emergency lights switch to the diagram.
Added the correct position of the alarm connector bridges to complete the electric chain.

And to trace links easier without gliding eyes through the wires mesh,
I coded all the incoming wires of each particular item up to a fuse.
For example if right headlight is not working, I proceed as follows:
it is item 23, having 3 incoming cables:
  - black-green coded m4- ( taking - from main connector pin 4 ), tracing main connector pin 4, it takes minus from engine earth item 69.
  - pink-red coded 27+ ( taking + from item 27, dip beam relay ), tracing dip beam relay, incoming cable is coded f8+ ( taking + from fuse 8 ), tracing fuse 8, incoming cable is coded mf3+ ( taking + from main fuse via pin 3 on main connector ).
  - blue-white coded 79+ or ( 78+high/35+ ), 29+/f7+ ( taking + from item 79, passing button or from item 78, position high, and item 35, light switch ),
                                                       both options traced further down to item 29, headlight cut out relay, and finally fed from fuse 7.

Initially it might look confusing,
but since I have no paper booklet in the top case,
just the diagram in the phone storage helps quite handy this way.

You may ignore the specific additions to my bike:
- the added consumers directly to the battery terminals
- the horn safety switch

I hope there are no confusing mistakes in the picture,
but anyway if there are any, let me know, so I can amend it as it should be.

[Sin_Tiger]

   good work. I'm sure that will be of help to a few.