Article [13] ST1300 - Fuel Pump Circuit - Fault Diagnosis

There is no indication the bike has HISS.
I did test it in right at turn-on. I hooked up the meter, then tuned it on.
I'm looking for bad earths, but haven't really found any except at the fuel pump, where the connector was corroded.
I'm still deep into this. I did confirm that the bk/wh wires at the coils do indeed get 12v when I turn it on. It did sit for a while, and there is evidence of mice. But I don't see any chewed wires. I have the ecu out now (I told you I'm in deep) but without the specialized wire harness, don't know of any tests other than the ground/ 12v test in the manual. I'm trying to figure out a way to make that test without the test harness.
I am thinking that the ecu is not letting the bike start. But whether it's because of a bad signal from some sensor, or the ecu being bad, I really don't know.
Is there a set of tests than can be done, like with some other vehicles, such as lookinf for resistance readings, voltage, etc when one does different things?
 
Andrew Shadow said:
I can't read the story on the advrider site because I don't have an account. Without knowing what is written there, my first question is- Are there any fault codes? If so, what are they?

My third question is- Did this motorcycle sit unused for any length of time? If it did, consider looking for damaged wires under the throttle bodies. These wires may have been chewed on by mice. If they have, one or more injector wires may be damaged rendering the injectors inoperative. If the injectors are inoperative, the ECM disables the fuel pump.
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I just dug out the air cleaner, and looked under the housing. Actually, I didn't have to look that far. Plenty of mouse damage under the housing, and several injector wires have been chewed on.
I used the shop-vac on it, cleaned it up, but I definitely need a new aircleaner- it's been chewed on the inside. I also need to closely inspect those wires. Several will have to be replaced.
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tlub said:
Plenty of mouse damage under the housing, and several injector wires have been chewed on.
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Mice damage is what I suspected, unfortunately. This is why the ECM has disabled the fuel pump. At least you know now.

If there are many damaged wires, you might consider just replacing the sub-harness instead of attempting to repair individual wires.

No ST1300's originally sold in North America, regardless of year, are equipped with the HISS system.
 
Ok, it's been a while since I posted, but thanks everyone. I replaced the harness with a good one, and what a wonderful sound when the fuel pump came on with the ignition on. It started right up, too. Then it was a long time to put all the Tupperware back on. I had removed way more than I needed, because I didn't know what I needed to get to. I rode it for the first time today, about 10 miles. It's a nice bike. I'll take it to Oregon in a week or two- at least that is the plan.
 
New member here.

Just making a post so I can be approved. (to post)

Question.

How do I start a new thread??

I have a 2006 St1300A with a no start. (pump doesn't prime??.)
 
Rockstar said:
New member here.

Just making a post so I can be approved. (to post)

Question.

How do I start a new thread??

I have a 2006 St1300A with a no start. (pump doesn't prime??.)
Click to expand...
Rockstar said:
New member here.

Just making a post so I can be approved. (to post)

Question.

How do I start a new thread??

I have a 2006 St1300A with a no start. (pump doesn't prime??.)
Click to expand...
 
Hi,

As my experience of this problem with engine cranking OK but no fuel pump priming. I'll briefly go through my fault finding procedure which was supported by Google AI (ai).


In order for the ECU to enable fuel pump priming the ECU needs to be able to read and satisfy itself the fuel level sensor is presenting a resistance in the range 6 Ohms to 220 Ohms. In my case it was presenting 54Mega Ohms which displeased the ECU and caused it to flash all 8 segments of the fuel gauge on and off constantly. Unfortunately it did not store a fault code for this error. You can eliminate the fuel level sensor by disconnecting the 2 pin blue connector by the lower rear end of the tank on the left hand side of the bike. You can verify you have found the correct connector by tracing its' path around the frame to the fuel level plate on the bottom of the fuel tank by raising the tank at the front end. With the cable disconnected at the connector, check the resistance of the 2 pins at the tank side. It should read in the range 6 Ohms to 220 Ohms depending on how full the tank is. If it reads higher or zero Ohms it will fail the ECU test.


To verify the sensor was faulty Google AI suggested I plug in a probe light tester with resistance around 160 Ohms across the socket pins leading to the ECU. I did this, switched on the ignition and the flashing Fuel gauge segments stopped flashing and showed a fuel level of 6 bars. The ECU was now satisfied that there was fuel in the tank and now enabled the fuel pump to run. I then removed the sensor from the tank by undoing the 4 nuts and found the wire to one of the sensors had become detached. I cleaned it and resoldered it. If you do resolder, the heat required will, if left too long, melt the plastic base so I would advise you clean the connectors well and use a high wattage soldering iron to make the connection short and localised. Alternatively buy a replacement.
 
Welcome @Mike Farrell . Good result - although I would not recommend using AI as a way of finding accurate information - but clearly it worked in this case.

A.I. gleans information that it finds from various sources and and puts together a composite. I have found that things that I have written on this and on other forums have been picked up by AI engines and come up with a summary - which while being an accurate representation of what it had located, had produced a summary that was not completely correct, or which was missing key points.

But it did reveal links to the original sources - which was handy.
 
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Mike - a while back you asked how you start a new thread. I don't think that you got an answer.
So here is one.

Menu bar at the top of most pages. Select forums.

Scroll down the list to the ST Forums section and (eg) ST1300 Related.

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Click on the topic which is most appropriate for the question or comment that you want to ask. If your contribution doesn't fall into one of those categories then click the header - ST1300.

The same topic headings will be listed - but underneath are topics that other people have created.
Below a screen capture of that page - reproduced and shrunk a bit for illustration.
Top right of that page is a 'Post Thread' button. Give your topic a title - bear in mind that it helps when searching if the title includes the key words for your topic.

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It also helps the people answering if your personal details include your bike make and model Eg ST1300 A9.
That can be added by clicking on your name on the blue banner at the top right, scrolling down the page for the row with the side heading 'Bike'.
That detail will then be placed alongside every post that you make - which is helpful to people answering - if they remember to look before posting their answer !

No guarantee - we don't always remember to look first. What ? Oh - just me then.
 
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