Autonerdz forums

I got a call to look at a 2003 TT600 which apparently stalled on the motorway at 70mph and rolled to a stop but restarted once the ignition was reset. The owner also thought it didnt feel right but this might just be his imagination.

I arrived and the bike was running perfect with no issues.  Quick test ride and all was good. no issues detected.

I then ran Tuneecu and read the fault codes which were:-

P0351
P0352
P0353
P0354
P1351
P1352
P1353
P1354

All the codes refer to the ignition primary for all 4 cylinders. Description was open circuit or short to earth.

I cleared all codes but could not replicate the issue. I disconnected all the connectors including the main engine harness under the tank, Both ECU connectors, checked engine management fuse, checked the main relay that controls ECU. I found no issues. Ive checked the loom for damage but cant see any signs of rubbing etc.

I even dug the scope out and had a look at the current ramping on the coils. All were around 6 amp peak and all looked good with no abnormal humps anywhere. all 4 looked the same.

Im at a bit of a loss which direction to go now with it. The bike has a datatool alarm so im thinking of bypassing this to rule it out. Ive seen these cause issues in the past.

Ive looked at the wiring diagram on the only thing that the 4 ignition coils have in common are the 12v feed. I also considered powers/grounds to the ECU which ive yet to check. I maybe need to check for current ramp on the injectors as its on the same circuit as the ignition coils so in theory if one was shorting internally it could bring the 12v down creating the codes but i would have expected to see injector codes too however im not too experienced with triumphs so who knows.

anyone got any other suggestions. Ive ruled out the 4 main ground side switches from the ECU to the coilpacks.

Here is the strange looking fuel pump amperage with no initial spike.

Pumps spinning approx 8500rpm which seems very fast compared to 3450rpm from the good known pump.

Update - I sourced a used pump as the owner didn't have the money for a new pump and fitted it this morning. Good news was it fired straight up. I checked rpm of the replacement pump which was around half the rpm of the original and its drawing about 3.5A with a good current spike when it turns on.

Yes I agree. Something sheered in the pump.

That's the way it goes sometimes but it also shows that sometimes fault codes can lead you up the garden path. I spoke with the owner a few days ago and he's covered over 500 mile with no issues. In fact he said it's starting better than it ever has. So that's good news.