Coolant Temperature and TuneECU Question

tribal

Moto Hobo Gypsy Vagabond
Joined
Apr 15, 2006
Messages
889
Location
North America - presently touring the USA
Ride
2005 Rocket III & 2015 Rocket III Roadster
Well, it's me again... Two steps forward & one backwards.

Bike ran excellent for several days (500+ miles with some in hot stop&go traffic) but overheated in traffic going to a "Back the Blue" police support rally 5 miles away this morning and it wasn't that hot out.

Symptoms/History:
- Overtemp light DID NOT come on.
- Outlet hose was clogged so it spewed out the overflow bottle cover onto my pipes for a nice smoke show pulling into the rally. Embarrassing to work on it in a crowd...
- Cleaned hose, added water & went home.
- Swapped the two black grounds going to the fuel pump (see related thread). No difference but I think I saw the low fuel light come on when the tank was raised.
- Noticed fan was not coming on.
- 10A Fuse 7 looked OK but I put in a new one.
- Swapped Fan Relay & Fuel Pump Relay and bike started fine.
- Check engine light was already on from a previous issue - Error = TPS, Injector 1, injector 2 voltage. That was AFTER I fixed the oil tank O-Rings.
- Ran TuneECU and fan test passed
- Started bike and noticed that the Temperature on the left side of the Diag screen read normal (went to 105C but fan didn't kick on) BUT, the virtual gauge started at 57C and didn't move more than 1C!!! Q. Is there more than one sensor? If so, which one does the ECU read?
- Checked radiator cap. Seems OK but I will order a new one.
- Pulled the plastic throttle cable protector as it looked like the Coolant Temperature Sensor wire may have been pinched. Reseated it in the connector & the other end seems inserted into the
thermostat engine area OK.

@DEcosse - this may explain the flickering of the LED lights in the previous diagnostic discussion wrt fuel sensor wire breaking..??

At this point I am going to order a new temperature sensor and the radiator cap.

Is there anything else I can do/fix/replace???
 
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Well, it's me again... Two steps forward & one backwards.

Bike ran excellent for several days (500+ miles with some in hot stop&go traffic) but overheated in traffic going to a "Back the Blue" police support rally 5 miles away this morning and it wasn't that hot out.

Symptoms/History:
- Overtemp light DID NOT come on.
- Outlet hose was clogged so it spewed out the overflow bottle cover onto my pipes for a nice smoke show pulling into the rally. Embarrassing to work on it in a crowd...
- Cleaned hose, added water & went home.
- Swapped the two black grounds going to the fuel pump (see related thread). No difference but I think I saw the low fuel light come on when the tank was raised.
- Noticed fan was not coming on.
- 10A Fuse 7 looked OK but I put in a new one.
- Swapped Fan Relay & Fuel Pump Relay and bike started fine.
- Check engine light was already on from a previous issue - Error = TPS, Injector 1, injector 2 voltage. That was AFTER I fixed the oil tank O-Rings.
- Ran TuneECU and fan test passed
- Started bike and noticed that the Temperature on the left side of the Diag screen read normal (went to 105C but fan didn't kick on) BUT, the virtual gauge started at 57C and didn't move more than 1C!!! Q. Is there more than one sensor? If so, which one does the ECU read?
- Checked radiator cap. Seems OK but I will order a new one.
- Pulled the plastic throttle cable protector as it looked like the Coolant Temperature Sensor wire may have been pinched. Reseated it in the connector & the other end seems inserted into the
thermostat engine area OK.

@DEcosse - this may explain the flickering of the LED lights in the previous diagnostic discussion wrt fuel sensor wire breaking..??

At this point I am going to order a new temperature sensor and the radiator cap.

Is there anything else I can do/fix/replace???
If your going to take her back apart for the temp sensor you might as well put a new thermostat in with its gasket.
 
Thanks Scott, I ordered Thermostat T2100715 for early '05 with the T2100713 O-ring plus some spare relays to get free shipping from AdeptPowerSports as I've lost faith in BikeBandit.
Hopefully I can get them by Friday...
I'm a little hesitant to add more work as it seems to lead to even more work but what the heck...

I still don't know why TuneECU reports two different temperatures off the same sensor.
 
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This is from the TuneECU site showing the Diagnostic Screen.
Temp on left and gauge show -25c .
On mine when warm they both started at 56C. The value on the left steadily went to 105C while the gauge counter only went to 57C.
It seems like the water temp sensor is reading correctly but the ECU is not seeing it?? Not sure...
86DC3966-B7BF-4459-B08E-2AE1D83AAE22.jpeg
 
The one in the left margin is the AIR temp sensor
The one on the dial is the coolant temp
It seems like you may have them swapped (although why they would both be starting at 56 is another mystery!)
 
Wow, I never noticed that pop up feature in TuneECU.
My Air Temperature Sensor is located in front of the 1st Cylinder K&N Filter
RIGHT ABOVE the Engine Coolant Sensor plug.
If the connectors are the same (I know they both have a wire lock) then It appears that I must have mixed them up when I reinstalled the throttle bodies last week.

In the immortal words of Forest Gump, “Stupid is as stupid does”.

I am returning tomorrow from dropping my last load of crap and my summer car off for storage and will swap the plugs.

It is still strange that it did not overheat Friday as I took it past 100MPH several times and spent a lot of time idling in higher temperature than on Sunday morning. Or maybe it did and plugged the overflow hose.
 
1,000 thanks to you guys!
I got home and swapped the air and coolant temperature plugs, started TuneECU , and started the bike.
Air temp was 25C and stayed there.
Coolant temp went up to 105 as normal and the fan kicked on.
Yeah!
I need to focus on the trailer so I will carry the replacement parts I ordered and install them at a later date...
 
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