Coolant Temperature Sensor Mystery

[Journeyman]

When you put it on tune ecu and start bike go to sensor page and watch your coolant temp sensor and when the fan does or not come on. This may show problem.

I think it's intermittent though like yours. It's running fine now. You mean even so- might show an issue? I'll give it a go.

Hoping to do a 4 - 5 day trip next week (to be determined). I just changed the oil and put on a new rear tire. What else does she want?

 

[Kevin frazier]

Yeah, after bike has cooled, put it on tune ecu and start the bike, watch sensor page for that water temp sensor, note what temperature fan comes on and shuts off. Let the fan come on a couple times and see if the water temp sensor is behaving as should (lets just 190 degrees fan should come on and off when drop down below thermostat capability) and telling fan when to turn on and when to turn off. If it was the water temp sensor its gonna be bad, bike should overheat, i bet not intermittent like that fan controller like nashvegas fought.

 

[Nashvegas]

But I'm wondering, since we were getting different codes, if I should change the coolant temperature sensor, not the Fan, PWM Controller.

My code was P0117 (coolant temperature sensor)
Your code was P1552 (cooling fan)

Did your bike seem like it was actually overheating? I would think so if the fan stopped working. It only happened to me once, so far, but the bike seemed normal, so wondering if I was just getting a false reading from a bad sensor.

Definitely overheating. In fact, on one occasion, didn’t turn it off soon enough and it was spitting out coolant. when I went into tuneECU, I could trigger both fans on with no problem. It was like the PWM Controller would have a hiccup every so often and ignore what the temperature sensor was telling it. I think if your temp bars are going up that part is working correctly. I wonder if they had a bad batch of PWM’s.

 

[TURBO200R4]

I think that only once in the last 30 years the the module/ecu said it was bad all the other time it blamed the sensors or actuators.
i have probably seen 100's of them bad
if you can get a resistance value you can use a resistor to check/to see if it reads correct on tuneecu as a test
you could use it value ? to trigger fan as a test. dont forget they get hot

 

[Nashvegas]

I think that only once in the last 30 years the the module/ecu said it was bad all the other time it blamed the sensors or actuators.
i have probably seen 100's of them bad
if you can get a resistance value you can use a resistor to check/to see if it reads correct on tuneecu as a test
you could use it value ? to trigger fan as a test. dont forget they get hot

Yep, I went down that rabbit-hole and it came down to the PWM “brain” not doing its job. But that’s not one of the checks. And, it got worse and worse. For $180 I figured it was easy money because the problem was becoming pretty serious/aggravating. She runs like a champ now.