2006 GT500ABS - Interesting Problem

[chrisrappl]

Tom,

To answer your questions:

The regulator is on the left below the ABS unit.

The ECU is on the right in front of the battery.

I have ordered a new ECU from our hosts at AF1.

It's in the US warehouse, so I should have it in a week or so.

[tomd]

I just wanna see if mines warm all time etc makes me nervous I cant be havin nuttin like this I had belly pan off yesterday and had the Buike on thee slip n slide Water toy kinda simulates a med rain on pavement Abosolutely nuttin happened in the 20 min it sat there on and off

[IAGolem]

I just wanna see if mines warm all time etc makes me nervous I cant be havin nuttin like this I had belly pan off yesterday and had the Buike on thee slip n slide Water toy kinda simulates a med rain on pavement Abosolutely nuttin happened in the 20 min it sat there on and off

It should be warm all the time, but not hot. It's an electronic device; when it works it converts electricity to heat...

[tomd]

This Am in Nc no sun out twas 73 degrees I had bike more or less apart everything I shot W temp gun measured 68-74 degrees sitting in overcast sky outdoors.Battery was warmest @77.. no boxes on bike showed anything intresting not eben the led red key flashing on n off . So Cool ... I know Electricity generates heat..

[chrisrappl]

I'm pretty sure that the ECU should be cool to the touch when the ignition has been off for a while.

I would expect it to be slightly warm while in use.

I took every relay and connector apart again yesterday, sprayed all the contacts with a high grade electronic contact cleaner, dryed them with compressed air and sealed them all with silicone high-dielectric grease.

What I noticed was that I could get the ECU to light the EFI light and even to run the fuel pump if I tapped on it or changed its orientation.

So I'm pretty sure that the ECU is defective.

It's either the ECU or the wiring at the ECU plug, which could be a problem. I think that may require a new harness, so here's hoping the new ECU corrects the problem.

In the meantime, I changed the engine oil and filter, air filter, transmission oil, and installed a new iridium plug (NGK CR7EIX).

The rear tire is squared off and both tires are almost 7 years old, so I ordered new tires while I was at it. I'll check the brake pads when I change the tires.

My dog (Molly) keeps watching me work on the scooter and can't understand why we don't go riding.

[IAGolem]

Sounds like you've covered all the bases we could think of. Now as long as Molly approves...

[chrisrappl]

[Bob Walker]

Their seems to have been a side car with a canine rider at most of the big rallys that I have attended. My dog wants one. I'll bet that your dog goes wild every time that you get the scooter out. Take a picture of the whole rig, scooter, dog, and all.

[williamr]

It sounds as though the issue is the ecu failing to boot itself.

Check the power to the ecu, and the ecu ground.

Also check all the interlocks, including the kill switch.

As the problem seems to have been caused by rain it's more likely to be the connector into the ecu than the unit itself. Try unplugging the ecu connectors, spraying both parts with WD40 and leaving overnight before reconnecting. Contact cleaners don't remove moisture.

Rob

[tomd]

good call will usually when an ecu dies thats kinda it wiggiling etc indicate a conn , issue or such,,

[IAGolem]

It sounds as though the issue is the ecu failing to boot itself.

Good call on the rest, but the only way to actually reboot the ECU is to remove power long enough to discharge (reset) the buffers for mileage, time, etc. The ECU doesn't completely shut down with short power interruptions; it "sleeps" by doing nothing but watching the immobilizer circuit for activity when you shut the scooter off (hence the small blinking red light). Momentarily shunting PWR to GND won't do the trick either...

[chrisrappl]

The new ECU arrived yesterday. Thank you AF1 Racing!

I removed the battery so that I could properly install and ground the new ECU, reinstalled the battery, turned on the key and all the lights did what they were supposed to do including the EFI light.

The fuel pump ran for a few seconds and stopped (must have been satisfied). I cranked the starter for about 3 seconds, but it did not fire.

I initiated the start sequence again and hit the starter and "Voila" it purred like a kitten.

I am not looking forward to trying to put all the body work back together, so I installed a new rear tire. It was a bit more involved thanI expected, but it's done.

Tomorow I'll try to put everything back together.

I don't know why the ECU failed.

I have cleaned and sealed every connector.

I might try to make a waterproof shield for the ECU connector since it faces forward.

I'm assuming that the false low resistance reading from the oil pressure switch somehow affected the ECU.

Maybe it had an existing internal fault just waiting to fail.

Maybe it is programmed to lock out the EFI after a certain length of time sensing low oil pressure.

I have cleaned and tightened the oil pressure switch connection and filled the boot with high dielectric silicone grease.

So, the bike now has:

A new ECU

New oil, filter, air filter, Iridium sparkplug, rear tire.

All connections cleaned, dried and sealed.

All relays tested and now identified as to their function.

Fuel pump removed and checked for upgraded hose and clamps

Missing fuel filler overflow hose installed so that I shouldn't smell gas anymore after I fill up.

I will keep the old ECU and maybe someday after it has sat around unpowered, I might try reinstalling it, but I really think it's shot.

The new ECU has an updated part number and possibly updated mapping.

Compared to the ECUs or ECMs on Japanese bikes, this ECU was quite reasonably priced. Of course, I've never had to replace an ECU on a Japanese bike, so...

[Rockynv]

What about mods to allow the belly pan to be reinstalled?

[IAGolem]

The new ECU arrived yesterday. Thank you AF1 Racing!

I don't know why the ECU failed...
Maybe it had an existing internal fault just waiting to fail...
I will keep the old ECU and maybe someday after it has sat around unpowered, I might try reinstalling it, but I really think it's shot...
The new ECU has an updated part number and possibly updated mapping...

Compared to the ECUs or ECMs on Japanese bikes, this ECU was quite reasonably priced. Of course, I've never had to replace an ECU on a Japanese bike, so...

Hey, I'm glad to hear your story had a happy ending. The old ECU is junk - trash it. Crappy Italian electronics, made by the lowest bidder. Everything has an "end of life." Consider yourself better off for the experience.

And I'd strongly recommend reinstalling the belly pan. It'll keep water and road debris (rocks, squids. etc.) from ricocheting around your scoot's innards.

[chrisrappl]

I bought the rig, sight unseen, off of Flea Bay a few years ago. It was 4 years old, with 1200 miles. It had been owned by an 84 year old man in Arizona. When it arrived, I found helmets, gloves, manuals, speed bleeders, sparkplugs, side car cover and complete carabiner packed away in the bags, trunk and sidecar. However, the belly pan had been removed for the sidecar installation and was not included with the bike.