ST1300 Quartet Harness Shorts Out

The quartet harness (accessories) shorts out after about 20-25 minutes and I loose power to the GPS, and power socket. After I let the bike rest it all comes back on. I've checked the harness out for wear or exposed wiring, it's in good condition. The wiring harness leading up to the harness is in good condition. I've cleaned the connectors with contact cleaner and the spades are tight. I've had the plastic off four times now trying to solve this issue.

All lights, gauges, and engine remain fully functional. The short only affects the accessories.

This all started after riding through some deep water last May. I'm thinking this caused some failure on a relay somewhere. I checked the wiring diagram and two suspects stand out to me; the ignition switch and the main relay. Before I start working with blind part replacement and really mess something up, I thought I'd query more knowledgeable folks for likely causes. I don't even rate novice with electrical issues.

Any ideas on a likely cause for the accessory harness to loose power after 20 minutes riding?

That sounds like a relay to me. The coil in the relay could be heating up, after a while, and then dropping out. That would tend to explain why it works after cooling down. But I have no clue as to where the relay might be.

Ride Safe
John and Janis

Does the ignition switch have coils? The ignition switch looks like a PITA with the 3 #10 Torx security screws and I would like to avoid that if possible.

Reginald said:

This all started after riding through some deep water last May.

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If there's water involved, my money would be on corrosion that's causing a circuit to break during thermal expansion. (This isn't a short; that would result in blown fuses that would need replacement before the circuits would work again.)

I'm thinking this caused some failure on a relay somewhere.

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Probably not the case here. The switched lines on the quartet harness are controlled by the ignition switch (via fuse F; E on non-ABS bikes) and the main stop relay (via fuse C; B on non-ABS). Both of those circuits power other things on the bike, and a failure in either would show elsewhere.

I would help to know how your accessories are wired to the quartet harness: Is your power socket the Hondaline model? Which connector/wire are you using to get the power for your GPS? What contact cleaner did you use to clean the pins in the connectors?

Reginald said:

Does the ignition switch have coils?

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The ignition switch is just a switch. Don't bark up that tree unless there are problems elsewhere on the bike.

--Mark

The quartet harness has several plugs - iirc, one is powered all the time, the others are switched. Does the whole harness go dead or just the gps and your power socket? Are both on the same harness plug? How did you connect to Honda's 'hitatchi' connectors? Did you grease your connections before making them (see below)?

Perhaps not relevant months later, but how deep was this water that you rode through? Did you blast through it sending water everywhere or did you putter through at low speed? Honda's connectors are loaded with grease to seal out moisture. The two halves of the connector are then mated, pushing them together wipes the grease off the male and female spades where they touch establishing the connection. The balance of the grease seals out moisture and prevents (retards) corrosion. However, this is not foolproof and some of the connectors usually corrode after some years. The grounds are also suspect and usually the first items to check.

Blrfl said:

If there's water involved, my money would be on corrosion that's causing a circuit to break during thermal expansion. (This isn't a short; that would result in blown fuses that would need replacement before the circuits would work again.)

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That was May with a very hot summer between then and now. Don't see how water could be in one of the connectors from 7 months ago and cleaning up connectors since. Anything is possible, but likely? I cleaned every quartet connector with CRC QD Electronic Cleaner and pipe cleaners then resealed the connector with dielectric grease on the outside of the connectors. All connectors are Hitachi.

Blrfl said:

Probably not the case here. The switched lines on the quartet harness are controlled by the ignition switch (via fuse F; E on non-ABS bikes) and the main stop relay (via fuse C; B on non-ABS). Both of those circuits power other things on the bike, and a failure in either would show elsewhere.

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This is a non-ABS ST. Looking at the wiring diagram the horn and rear brake light switch are connected though the main stop relay. If I'm reading the diagram right, I don't see any other features that would fail. I never tested those. I guess I need to recreate this (go for a ride) and see if the horn works when the accessories give out.

Blrfl said:

I would help to know how your accessories are wired to the quartet harness: Is your power socket the Hondaline model? Which connector/wire are you using to get the power for your GPS? What contact cleaner did you use to clean the pins in the connectors?

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Honda socket, Honda Heated grips, and my Garmin. All use Hitachi connectors. Cleaner: CRC QD Electronic Cleaner

Thanks for your response and an idea to prove or discount a main stop relay failure. If you have another connector that could be cleaned in mind, I'm open to it.

Blrfl said:

The ignition switch is just a switch. Don't bark up that tree unless there are problems elsewhere on the bike.

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SMSW said:

The quartet harness has several plugs - iirc, one is powered all the time, the others are switched. Does the whole harness go dead or just the gps and your power socket? Are both on the same harness plug? How did you connect to Honda's 'hitatchi' connectors? Did you grease your connections before making them (see below)?

Perhaps not relevant months later, but how deep was this water that you rode through? Did you blast through it sending water everywhere or did you putter through at low speed? Honda's connectors are loaded with grease to seal out moisture. The two halves of the connector are then mated, pushing them together wipes the grease off the male and female spades where they touch establishing the connection. The balance of the grease seals out moisture and prevents (retards) corrosion. However, this is not foolproof and some of the connectors usually corrode after some years. The grounds are also suspect and usually the first items to check.

Click to expand...

I'm not using the constant powered part of the harness or the nine pin connector. I have the Honda socket, Honda heated grips and Garmin on the Harness.

I thought the water was an inch maybe two, but no it was six inches at least and I hit it way to fast. Did you know you can create a water fall with the ST? It went 3 to 4 feet above my windshield and smothered me with water. I didn't need a shower that night. The amazing thing is nothing failed as a direct result. It wasn't until weeks later the intermittent power failure occurred. I guess corrosion of a relay maybe. Like I said I'm open to most Ideas since I'm not proficient at electronics.

Reginald said:

Did you know you can create a water fall with the ST?

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Ha Ha, I did that in a Jeep years ago, got soaked, and didn't impress the girl I was with.

Electrical problems... they're the best! The first tool I turn to when trying to diagnose an electrical problem is the wiring schematic, unfortunately the schematic in the shop manual is monochromatic, with really teeny tiny lines. Fortunately we have a much easier to read wiring schematic available right here in the Article Repository, which can be downloaded, and viewed with any .pdf viewer.

Looking at the wiring schematic view of the Quartet Harness, we can see that two different circuits are sourced for switched power (12vdc). One of the switched power circuits is sourced by way of the Ignition Switch, as this circuit also provides power to the dash console, you probably would have noticed the dash console misbehaving at the same time you were loosing the accessories. The other switched circuit is sourced by way of the Main Stop Relay, which as Mr Blrfl has pointed out also provides power to the brake lamp circuit, and the horn circuit. Attempting to use the horn the next time the accessories have stopped working will aid in determining if the issue is the circuit failing (from the Main Stop Relay), or if the problem is specific to the accessory circuit beginning at the Quartet Harness.

Don't forget to check the chassis ground connections, though your accessories don't appear to be high current draw items, Honda didn't allow much extra current capacity in the wire harness.

Just got back from testing the horn theory. When the Garmin lost power, I tried the horn. It was working and nice and loud. I also tested the hazard lights and turn signals to which the harness is wired in the schematic. All these items worked. When I got to the garage I tested the rear brake light from the rear brake peddle and the lights worked fine. OK, it seems the relay is fine.

Hmm, the one thing I didn't test on this ride was the heated grips. I need to do that to see if I can isolate the problem to a specific area in the harness. It'll be tomorrow before I get to a test ride.

Anna'sDad said:

Don't forget to check the chassis ground connections

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Huh, where would that be located? I've looked for the ground but couldn't identify where it was. Didn't see it in the manual either, probably missed it. Thanks.

Anna'sDad said:

The first tool I turn to when trying to diagnose an electrical problem is the wiring schematic

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That's where I looked once I had every connection clean (But ground!). It's why I thought just maybe something simple like a relay replacement would work under the side cover.
And why I tested the front brake light switch to test the ACC switch in the ignition. The brake lights came on following the failure.

By the way it was beautiful riding weather, clear and 81 F. Would have gone much further if not for the electrical problem.

Regarding your puddle, it is possible that the water got into a contact and corrosion set in, I think that is the only point we are making. If something electrical got wet, it could take a while to corrode and misbehave.

And it sounds like you did all the right stuff with the contact cleaner and grease. Have you opened the connectors and pushed them together (on the quartet harness)? If you've done that with no change in the problem then clearly the issue is elsewhere.

Regarding the schematic Anna's Dad linked. I can call it up and enlarge it somewhat, but there is a limit - bottom line is it is not very useful for me. My manual is better. For my last bike (an old Guzzi) I printed out the schematic from a pdf file and then, using my copier, enlarged it onto 4 pieces of 11 x 17" paper. Then I trimmed and taped it together. Now THAT was very useful - until I bumped against the limitations of the generic diagram compared to my specific year bike.

Anna'sDad said:

Don't forget to check the chassis ground connections...

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Given how he got splashed, this is a good idea.

Reginald said:

I need to do that to see if I can isolate the problem to a specific area in the harness.

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Others have covered anything else I could contribute, but this is pretty much the way to diagnose most problems. Guessing is expensive and time consuming, which is why I tend to ask enough questions to rule out as many possibilities as I can.

--Mark

Reginald said:

Just got back from testing the horn theory. When the Garmin lost power, I tried the horn. It was working and nice and loud. I also tested the hazard lights and turn signals to which the harness is wired in the schematic. All these items worked. When I got to the garage I tested the rear brake light from the rear brake peddle and the lights worked fine. OK, it seems the relay is fine.

Click to expand...

That sounds like a productive ride, even if it was unbearably hot! Here in NJ I keep dodging the icy patches on the roadway.

Reginald said:

Hmm, the one thing I didn't test on this ride was the heated grips. I need to do that to see if I can isolate the problem to a specific area in the harness.

Click to expand...

Now that's a great excuse to get another ride in!

What are you going to do if the heated grips don't shut off when the Garmin does? Before you go tracing out the specific wires that link the Garmin to the Quartet Harness, you may want to test the Garmin, and the Garmin adapter cable in another vehicle. Try to eliminate the easy pieces of the puzzle before tackling the awkward pieces.

SMSW said:

Regarding the schematic Anna's Dad linked. I can call it up and enlarge it somewhat, but there is a limit - bottom line is it is not very useful for me.

Click to expand...

That's odd. Perhaps you're trying to zoom in on the schematic icon?

After you choose the schematic ST1300/A, or ST1300, don't bother with the image that is presented in the new window, rather use the download symbol centered above the image to download the schematic to your computer. Now that the file is saved to your computer, you may use the .pdf viewer of your choice (I prefer Foxit Reader, but any .pdf reader will do fine). Now you should be able to zoom in, and zoom out, rotate in any direction, as well as print to one sheet (larger is better), or print to multiple sheets, and tape the sheets together. The .pdf format is a pretty good format for this type of drawing, unfortunately at extreme zooming the text (especially the small text of the connectors) does not zoom well, and the text begins to overlap.

I have been touching on this thread for a couple of days. It has occurred to me that the original description of the problem is the Quartet shorting out. However no where is there a mention of the fuse servicing the quartet blowing. Also since the quartet powers the other accessories and the fuse that serves the quartet powers the turn signals (which apparently continue to work) it doesn't sound like a short but does sound like an intermittent connection. Check the plug for the gps (mine was assembled myself from eastern beaver components) where it plugs into the quartet.

Well, I took the bike out today and there were no failures. Rode the bike for over an hour. Had to take care of some business so I couldn't ride longer.

Now what's different about today? It was 10 degrees cooler, 69 degrees. Mark mentioned thermal decoupling (I think that's what he wrote earlier) and maybe it didn't get warm enough for that to happen. So I let the bike idle in the garage for 8 minutes (yes the garage door was open). No failures. Previously it's always failed within 25 minutes. Huh.

I looked in the manual again for the ground location and couldn't find it. Funny how I've found things others haven't seen and I can't find the ground. If I knew where it was I'd clean it.

Anna'sDad said:

you may want to test the Garmin

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Will do. The adapter cable is wired into the accessory harness and not compatible with the car. I do have a car mount for it and will test the Garmin on it. That will at least examine the Garmin.

I've ordered a $10 waterproof volt meter, some 3 pin Hitachi connectors, and a nine pin Hitachi connector. I'll make a jig plug for the voltmeter to test before the harness and the connections at the end of the harness. I'll make connections on the jig plug for both the switched and constant power. Hopefully I can find it with this rig. I just don't believe it's fixed itself today. I can also use the voltmeter once all this is fixed, if I can find a place to mount it.

Just to review, I've cleaned every connector on the harness and all wires were firmly connected to the respective blades and female connectors. All fuses are intact and have been cleaned. I don't think it's a short either. I've examined the quartet harness and most of the main harness ( a small portion passes between the frame and engine I couldn't get to) back to the fuses. An intermittent connection, I could believe this. Know of a way other than replacement to find it? When I first hooked up the Gamine in 2008, I put the blades in the Hitachi connector backwards and it had an intermittent connection. I had that fixed within two days by comparing plugs and seeing which direction the notch faced. The Garmin had been reliable until this. My accessory plug also failed at the same time the Garmin did. Leading me to believe it's a harness issue.

I really appreciate all the input, it's given me some ideas. And if anything else comes to mind, please let me know. I really want to travel somewhere this year.

Reginald said:

Funny how I've found things others haven't seen and I can't find the ground.

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It's that stuff underneath your feet.

Sorry, couldn't resist.

ibike2havefun said:

It's that stuff underneath your feet.

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Found it a few times with my face too. As recently as Lubbock in June.

Reginald said:

Found it a few times with my face too. As recently as Lubbock in June.

Click to expand...

Not having met you I was prepared to give you the benefit of the doubt. Now, not so much.

Anna'sDad said:

That's odd. Perhaps you're trying to zoom in on the schematic icon?

After you choose the schematic ST1300/A, or ST1300, don't bother with the image that is presented in the new window, rather use the download symbol centered above the image to download the schematic to your computer. Now that the file is saved to your computer, you may use the .pdf viewer of your choice (I prefer Foxit Reader, but any .pdf reader will do fine). Now you should be able to zoom in, and zoom out, rotate in any direction, as well as print to one sheet (larger is better), or print to multiple sheets, and tape the sheets together. The .pdf format is a pretty good format for this type of drawing, unfortunately at extreme zooming the text (especially the small text of the connectors) does not zoom well, and the text begins to overlap.

Click to expand...

Ahhhhh hah! Thank you, Thank you, Thank you!

Looking for the ground point so I can clean it up. I found a picture on the internet that shows about four (maybe more) lines attached under the rear of the gas tank and bolted to the frame. Looking at the area with the seat removed on my bike it looks like I need to remove the gas tank and probably the air box to get at the ground. Can someone confirm this for me before I start removing everything? Is there a short cut method?

Check this recall attachment.
That ground?

https://www.st-owners.com/forums/attachment.php?attachmentid=130351&d=1356972413