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Did the ground test on the gauge, it worked, got a new temp sensor but does not register a reading when I ride for 10+ minutes, any ideas?
Firstly: I fixed your title from "Cooing" to "Cooling". Hope you don't mind.

Is there any possibility that the wire from the temp sensor to the gauge is faulty? Corroded? Broken?
 

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Discussion Starter · #3 ·
Firstly: I fixed your title from "Cooing" to "Cooling". Hope you don't mind.

Is there any possibility that the wire from the temp sensor to the gauge is faulty? Corroded? Broken?
I would hope not, i also tested the ground with the wire holding it to the engine block, temp housing and frame, every time it had the temp gauge slowly climb to "H". The only thing I didnt test was suspending the sensor while connected in hot water only because its brand new
 

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I would hope not, i also tested the ground with the wire holding it to the engine block, temp housing and frame, every time it had the temp gauge slowly climb to "H". The only thing I didnt test was suspending the sensor while connected in hot water only because its brand new
I've found new doesn't always mean it's good. I'd test it.
 

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Discussion Starter · #6 ·
Agreed. At a minimum, to know for sure that it's doing it's thing. If he's in a cold climate, could it possibly be that the coolant isn't getting hot enough to move the gauge?

Are the fans kicking on?
I'll test dunking the sensor in hot water another day, its already late and i put the damn thing together like 3 times today already😭 And it sure gets plenty warm enough here, mid day its in the 70s-80s, 50s-60s at night, so besides a bad/new sensor, I'm vexed. As for the fans, I can confirm that yes they do work as they have been test grounded as well, as for wether or not theyre doing their job when they feel like it, i wouldnt know as the gauge isnt giving me any info to go off of.
 

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As far as possible wiring problems I cannot remember if there’s two connections between the temp sensor and the gauge. One under the plastic side covers on the neck and another in the housing to connect the gauge. I feel like when I tested the temp guage I tan the ground test from two different points.
 

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As far as possible wiring problems I cannot remember if there’s two connections between the temp sensor and the gauge. One under the plastic side covers on the neck and another in the housing to connect the gauge. I feel like when I tested the temp guage I tan the ground test from two different points.
The color wiring diagram shows the black/yellow ground shared with the temp gauge, tach, and tach light.

The yellow from the temp sender changes to yellow/white that runs to the temp gauge from the plug under the neck cover.

The brown at the temp gauge is shared several places, including the tach and the horns. The brown originates at the RR, and also powers the JB and front brake light switch.


If these shared components are working, my money is on a defective new temp sender.
 

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The color wiring diagram shows the black/yellow ground shared with the temp gauge, tach, and tach light.

The yellow from the temp sender changes to yellow/white that runs to the temp gauge from the plug under the neck cover.

The brown at the temp gauge is shared several places, including the tach and the horns. The brown originates at the RR, and also powers the JB and front brake light switch.


If these shared components are working, my money is on a defective new temp sender.
Something doesn't add up, at least to me...

If the temp sensor (thermostat, right?) is functioning well enough to cause the fans to kick on, then that kind of eliminates it as being faulty, right?

Therefore, is it possible that the gauge itself is faulty? I know he said he did the ground test and the gauge went to the Hot side, but that would be more of a direct on or off signal, versus a degree of signal.

Still trying to learn this method of deduction and process of elimination, so I might be way off base here...

:elmo:
 

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Something doesn't add up, at least to me...

If the temp sensor (thermostat, right?) is functioning well enough to cause the fans to kick on, then that kind of eliminates it as being faulty, right?

Therefore, is it possible that the gauge itself is faulty? I know he said he did the ground test and the gauge went to the Hot side, but that would be more of a direct on or off signal, versus a degree of signal.

Still trying to learn this method of deduction and process of elimination, so I might be way off base here...

:elmo:
He's tested the gauge, it works, the ground and sender wire is working.

The thermostat, temperature sender, and fan switch are three separate parts. So the gauge will work independent from the fan.

It just looks like the weak link is the temp sender. He probably began with a faulty sender, then installed a defective new one.

Edit: the temp sender should begin to vary the resistance as the temperature rises. Ohms will change as it heats up.

One test that you can do is continuity in the sender. Ohm meter probe on the wire terminal (with the sender disconnected), and one probe on the threads of the sender. If it's open, it's no good.

If it's not open, then you can test ohms with the sender in a pan of water brought to a boil.
 

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He's tested the gauge, it works, the ground and sender wire is working.

The thermostat, temperature sender, and fan switch are three separate parts. So the gauge will work independent from the fan.

It just looks like the weak link is the temp sender. He probably began with a faulty sender, then installed a defective new one.

Edit: the temp sender should begin to vary the resistance as the temperature rises. Ohms will change as it heats up.

One test that you can do is continuity in the sender. Ohm meter probe on the wire terminal (with the sender disconnected), and one probe on the threads of the sender. If it's open, it's no good.

If it's not open, then you can test ohms with the sender in a pan of water brought to a boil.
Okay, I had to take a peek at the diagram to make sense of it. I was thinking (incorrectly) of the entire thermostat assembly as one unit... Duh, I should know better, I took my thermostat out and checked it with boiling water, remember? (Turned out I just had some leaking hoses.)

Well that sucks that the new one is crap. I'd be a little pissed. I'd demand a replacement AND a refund. "Send me a new one for free, and refund my money - including shipping - too!"
 

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Okay, I had to take a peek at the diagram to make sense of it. I was thinking (incorrectly) of the entire thermostat assembly as one unit... Duh, I should know better, I took my thermostat out and checked it with boiling water, remember? (Turned out I just had some leaking hoses.)

Well that sucks that the new one is crap. I'd be a little pissed. I'd demand a replacement AND a refund. "Send me a new one for free, and refund my money - including shipping - too!"
A long time ago you could trust new parts. After getting stuck a few times I finally learned to back up and test new parts when a repair goes wrong. I've had it happen so many times, it's the first thing I do now. The customer is quality control now. Send out a million parts, 5000 come back defective.

Of course we don't know yet, but I would bet on it.
 

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A long time ago you could trust new parts. After getting stuck a few times I finally learned to back up and test new parts when a repair goes wrong. I've had it happen so many times, it's the first thing I do now. The customer is quality control now. Send out a million parts, 5000 come back defective.

Of course we don't know yet, but I would bet on it.
I think this holds true for most industries, my first job out of tech school was a PC bench tech for a local shop. If I wasn’t pulling cable, I was building custom PC’s, I would say 2 of every 10 components needed to be RMA’d. So it’s never a shock when anything shows up DOA.
 

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I think this holds true for most industries, my first job out of tech school was a PC bench tech for a local shop. If I wasn’t pulling cable, I was building custom PC’s, I would say 2 of every 10 components needed to be RMA’d. So it’s never a shock when anything shows up DOA.
It's funny you said that... I'd forgotten how many power supplies, cooling fans and optical drives I had to return. I always just chalked it up to poor shipping practices. Now that I think about it, there were always at least one out of every ten mobos that were buggered.

I guess it's like Spockster said, the consumer has become quality control.
 

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Discussion Starter · #15 ·
I've found new doesn't always mean it's good. I'd test it.
Hey everyone, I finally got around to changing out the thermostat and testing another new temp sensor by suspending it in boiling water and still nothing on the gauges.. I also tried holding the plug while commected to the newer sensor to ground and again, the gauge slowly began climbing so the connection is solid.. Im at a loss of ideas at this point
 

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Hey everyone, I finally got around to changing out the thermostat and testing another new temp sensor by suspending it in boiling water and still nothing on the gauges.. I also tried holding the plug while commected to the newer sensor to ground and again, the gauge slowly began climbing so the connection is solid.. Im at a loss of ideas at this point
Do you have an ohm meter?

You tested the sender by putting it in hot water while connected to the bike?
 

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If the sender wasn't grounded when you put it in the water, it wouldn't read on the gauge. If you only had the gauge wire connected, it wasn't grounded.

The resistance numbers should be in the manual, but as long as you see the reading increase as it gets hot, that's all that matters.
 

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Discussion Starter · #19 ·
If the sender wasn't grounded when you put it in the water, it wouldn't read on the gauge. If you only had the gauge wire connected, it wasn't grounded.

The resistance numbers should be in the manual, but as long as you see the reading increase as it gets hot, that's all that matters.
Oh yea, the numbers did change so i knew it was doing something but even when I pit it all back together and let it idle for a good 6-7 minutes, the temp gauge still never even budged
 

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Oh yea, the numbers did change so i knew it was doing something but even when I pit it all back together and let it idle for a good 6-7 minutes, the temp gauge still never even budged
Hmm. gonna have to think about this one.

Gauge works when grounded, sender changes with heat, but it doesn't work.

Are you using teflon tape on the threads? Sometimes that can prevent a good ground.
 
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