ST1100 Turn signals don't flash when hot

RobsTV

RobsTV

Joined
Jan 26, 2008
Messages
238
Location
New Port Richey, Fl.
Bike
'93 ST1100
Turn signals work fine when bike is cold (Florida 85 degree cold). After 10 minutes of riding they stop flashing and just light up the side I select. Shut off bike for couple hours and again fine for a short time, then no longer flash. Most searches I see temperature related are for no flash when cold.

Thinking relay? Can it be serviced or replace with generic that simply needs rewired?

Thanks
 
Hi Rob:

It is most likely the relay, the fact that the bulbs illuminate when they stop flashing rules out any wiring problems.

The relay is, I believe, "generic", to the best of my knowledge, it is not a unique Honda part. I believe that the turn signal relay is located in the same area as the fuses and battery, on the left side of the motorcyle - but it might be on the other side, up high, about the same distance back as the battery. See the parts diagram below.

Here is a link to another discussion that might provide useful information:
Front Left Turn Signal Not Working (ST1100)

Michael

ST1100 Wire Harness
Diagram Source: Partzilla "Wire Harness 2" Diagram
1100 turn signal relay.png
 
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Anything that affects both sides the same must be ahead of the turn-signal switch. The flasher is the primary suspect.
 
Anyone know where the ECU is located on '07 ST? I'm looking to install a gear position indicator from HealTech. Need to find the ECU for the connections. What do I need to remove to get to it?
Thanks for the help!
Alan
 
It's a three pin connector. Also have to locate a yellow wire with green stripe. Any diagrams out there showing this?
 
I'm thinking the turn signal relay in the diagram above is also know as a flasher. Dunno what/if the difference is here. I replaced that part a short time ago when I added LED bulbs. It is located behind the RIGHT sidecover. Should be able to identify it easy by the rubber holder and downward pointed connector about the middle of the bike close by the wire harness. I can take a pic if need be.

I can mail you a know working flasher if you like. Also could order one from Amazon cheaply. Then if in the future you upgrade to LED turn signal bulbs you will be good to go.

https://www.amazon.com/gp/product/B073J82PNF/ref=oh_aui_search_asin_title?ie=UTF8&psc=1
 
ATA said:
Anyone know where the ECU is located on '07 ST?
Click to expand...
Hi Alan:

The ECU is located in the tail of the motorcycle. Remove the seat to get access to it. It is behind / underneath / nearby the little storage compartment that you see at the extreme rear end of the motorcycle once you take the seat(s) off. Here's a link to a YouTube video that discusses turn signals, but shows the location of the ECU - it is what the narrator of the video calls the "computer boxes". ECU Location Video

Here is a link to an excellent wiring diagram: ST 1300 Wiring Schematic

Michael
 
Thanks for all the replies.

Amazon link was very helpful, showing 2 wire relay works and "The Cheese" review notes it is a direct plug in without modding. Perfect, have one on its way! Also, thanks for the offer of sending a test part.
 
CYYJ said:
Hi Alan:

The ECU is located in the tail of the motorcycle. Remove the seat to get access to it. It is behind / underneath / nearby the little storage compartment that you see at the extreme rear end of the motorcycle once you take the seat(s) off. Here's a link to a YouTube video that discusses turn signals, but shows the location of the ECU - it is what the narrator of the video calls the "computer boxes". ECU Location Video

Here is a link to an excellent wiring diagram: ST 1300 Wiring Schematic

Michael
Click to expand...

BTW, This is the ST1100 Forum. For a ST1100, the ECU is located in the left side, next to the headlight.

And I don't know how a gear position indicator can be installed on a ST1100.

Back to the original post : I installed an automotive LED flasher after I installed LED lamps. Had to cut off the OEM connector, change the connector and re-wire.
 
Update:
Purchased the 2 wire LED flasher The Cheese suggested above and it was a direct plugin replacement. No wire cutting or modding needed. Works perfect and problem solved. Thanks guys.
 
Jim Van said:
BTW, This is the ST1100 Forum. For a ST1100, the ECU is located in the left side, next to the headlight.
Click to expand...
Hi Jim:

You are absolutely right, my apologies. I own one of each (1100, 1300) and I guess I confused the two when I posted that reply.

Michael
 
Question? My left turn signal works ok but the right one takes five seconds before it will start blinking....do you think its the relay? only does it when its cold outside.
 
red one said:
Question? My left turn signal works ok but the right one takes five seconds before it will start blinking....do you think its the relay? only does it when its cold outside.
Click to expand...
Could one bulb be not working, or a different bulb type?
 
Larry Fine said:
Could one bulb be not working, or a different bulb type?
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No I checked the bulb and it flashes both front and rear. It just delays for about 5 seconds only when cold. My clock light works sometimes. sometimes not. I just chock it up to old age. Just like me stuff don't work the same as it use too;)
 
red one said:
Question? My left turn signal works ok but the right one takes five seconds before it will start blinking....do you think its the relay? only does it when its cold outside.
Click to expand...
I'd put money on a dirty/worn indicator switch.
Take it apart and clean it. Might be an idea to photograph the bits before they explode over the workshop.
When reassembling take note of the handlebar dimple.
Hope it helps.
Upt'North.
 
Upt' North said:
I'd put money on a dirty/worn indicator switch.
Take it apart and clean it. Might be an idea to photograph the bits before they explode over the workshop.
When reassembling take note of the handlebar dimple.
Hope it helps.
Upt'North.
Click to expand...
Thanks North this spring when I pull it out from hibernation I am going to trouble shoot it and try that.
 
since the relay is common to both left/right, that wouldn't seem to be your issue, it should work the same way for either side. I'd be more inclined to investigate the bulbs first as Larry suggested. You may have a weak bulb that's causing the issue. Just because they both light up doesn't mean there's not something marginal in one or both of the bulbs that delays the current draw needed to trigger the relay. I wouldn't rule out the switch, but I'd look at that second.
 
dwalby said:
since the relay is common to both left/right, that wouldn't seem to be your issue, it should work the same way for either side. I'd be more inclined to investigate the bulbs first as Larry suggested. You may have a weak bulb that's causing the issue. Just because they both light up doesn't mean there's not something marginal in one or both of the bulbs that delays the current draw needed to trigger the relay. I wouldn't rule out the switch, but I'd look at that second.
Click to expand...
Those bulbs are the original ones so it probably could not hurt. when I order my air filter and sub filter from my dealer I may get the bulbs too.
 
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