Triumphrat

x75

one day my 595 did not buzz when the key switched on and refused to start, everything else worked OK just will not fire up. Replaced the fuel pump to no avail, did not find any voltage to pump, so replaced the pump relay a couple times, still no power to pump - everything else lights up fine. any hints? thanks I'd like to get it running again.

DEcosse

First question - is neutral light on?

At your Fuel Pump relay socket, check for +12V at both the Purple and Green/Red wires:

Purple should be 'hot' all the time, even ignition 'off'; Green/Red should be 'hot' with ignition on & Kill to 'run'

Volts to Purple comes off Fuse 8

Volts to Green/Red comes from:
battery + -> Fuse 9 -> White wire -> Ignition Sw -> Green Wire -> Kill/Run Sw -> Green/Brown wire -> Fuse 1 -> Green/Red wire -> Alarm bypass connector -> Green/Red wire -> Ignition Distrubution*

* Includes Neutral/oil lights, Fuel Pump relay, Starter button, ECM

If you have power to both those wires at the ECM (also make sure the correct relay is installed in that slot!!) then the Black/Purple should go 'low' when the ignition first turned on for 3 secs**
** important you measure for this - and also the output voltage from relay at the purple/white wire - during the first 3s after ignition on - flip kill off & on if you need to retest.
After 3 secs that signal will go high again anyway.

If you have the two input power available but ECM output drive (Black/Purple) does NOT go low, look for issues on the grounds.
See issues surrounding the Ground Block connector.
Also check that Main Power relay is switching on.

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Hangover

Have you checked the 15A fuel pump fuse ?

bradtx

That's fuse #8 in the above post.

X75, Is there an alarm unit on your bike?

Brad

x75

Thanks to everyone for trying to help. I have just again tried to repair the motorcycle – been busy with work and lost my laptop to a bad motherboard recently. Anyway I have been back on the problem today.

I do not have an alarm, and yes the neutral light illuminates when the key is turned on. Fuse 8 is fine.

Also I may have messed things up when I first encountered the problem. I looked in the shop manual, saw the cluster of relays under the seat and swapped their positions to see if perhaps the relay was bad – it made no difference on the problem, but now I don’t know which relay is which. They are externally identical as far as I can tell, same BOSCH number, same pins, same diagram on the side, everything - is there a way to distinguish the appropriate relay?

So here’s what’s going on.

At my Fuel Pump relay socket, I found +12V at the Purple/Green, and when switched on 12V at the Green/Red wire.

I have power to both purple wires at the ECM Main Power Relay, however I’m NOT sure the correct relay is installed in that slot!

By swapping relays/positions I was finally able to cause the Black/Purple on the Fuel Pump relay to go 'low' when the ignition first turned on for 3 secs, then it jumped to about 6.8 V. After turning off the key switch, voltage holds at 7.25 for a few seconds then an audible click is heard from the relay and voltage drops to zero. The output voltage from the Fuel Pump Relay at the Purple/White wire never gets above 0.25 volts. So maybe the Fuel Pump relay really is the problem.

12V is available for the two purple wires on the ECM Main Power Relay, also on the Yellow/Brown when the key is off. Once the ignition is switched on, Yellow/Brown goes to about .25 volts in concert with the Fuel Pump relay voltage cycling on Black/Purple; also the Brown/Pink wire gets full voltage.

That’s the story with the current permutation for the 3 identical relays. I did study the BOSCH relays and they have small numbers stamped in the sides, and these numbers are different for each relay. I don’t know if I’m looking at a date/batch code or perhaps a specific application identifier. I know that voltage behavior for the various wires varies with relay permutation.

Is there a way to test each relay, and to determine its intended application?

Thanks, I want to ride the old T595 so badly. I placed an order for it long before they were available (in 1995 I think) and I got one of the very first ones built, back when they were still polishing the frame at the factory. My dealer told me they quit doing that after the first week, and subsequently changed to simply painting the frames, so only a handful were built in that manner. It still has less than 5000 miles on it.

TriumphMuscle

Sounds like you've got a great bike!
I'm definitely gonna stay tuned since I'm having the same issue on my '00 sprint.

DEcosse

Yours is quite different circuit - has no relay.

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x75

I have found 3 new BOSCH 0332014112 relays for less than $35 total so I am just going to replace them all.

x75

Well - it runs! or rather it ran for a while. I installed three new relays, checked that the fuel pump buzzed, then added gasoline and it fired up - after sitting for 5 years or more. I rode a little ways up and down my street, checked other fluids and decided to take a ride. 8 miles to the gas station, no problem, so I headed into town to see my girlfriend, a one way trip of 28 miles - no problem. Next morning I head home, bike fires right up, runs about 4 miles then while sitting at a red light - stops dead in it's tracks like hitting the kill switch. All lights are fine, fuel pump is buzzing, starter spins strong but no fire. I remove the seat, wiggle all the new relays - nothing. I end up fetching my trailer and towing it home. I'm stumped, so I will search the forum for dead spark issues....

Sure was fun to drive it again, if only for about 50 miles...

DEcosse

Take a look at your ground block - you'll find a plastic block in your battery box region where all your grounds come together

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