1999 GL-1500 temp gauge not working.

[Drdoom]

I removed the fan from the right side of the bike as sitting on the bike. i could not fine a temp sender with a single wire. i did find a sender or sensor that had a double wire brown green.It Didn't seem to have anything to do with the temp gauge.
That sender I'm looking for is on the right side while on the bike Correct??? and is a single green/blue Correct???
I need some help and I appreciate the help.

[Rambozo]

Left side of the thermostat housing.

[Drdoom]

I found it on the left side. Removed the fan. After that it is fairly easy to get to. I grounded the wire and found the gauge to work perfectly.
So I’ll be replacing the sender.
Thanks everyone.

[Drdoom]

I stopped by a Cycle part store and picked up a new thermo sensor.
Thanks

[Drdoom]

I replaced the thermosenser with a new one that was an aftermarket one and put it back together rode the bike for a few blocks and the gauge didn't work. So I order the OEM part from Honda and put it in and it also isn't moving the needle. I didn't have time to ride it. I checked the #8 fuse. it is fine. I also checked the main fuse by the battery and it is good. It also says to check the #3 relay. I looked at it and you cant tell by looking if it is good or not. I will say the heat gauge needle moved to hot when grounding the green/blue wire. So I'm not sure where to go next
I tested the cooling fan system and it is working.

[DenverWinger]

Without looking at service manual seems that the temp sensor goes into the Thermostat housing, I recall a post where the Thermostat housing lost its continuity to ground due to corrosion on the housing attaching screws and having a gasket between the housing and the engine block causing temperature sensor not to work due to no ground.

Try running a ground wire to the thermostat housing and see if that does anything, or slightly loosen/retighten a thermostat housing screw to knock off the corrosion.

[Drdoom]

Thanks I’ll give that a try. A really good idea.

[Drdoom]

Well its been a couple weeks, I checked out the grounding of the thermostat housing and it is totally grounded.
I could touch the gauge wire to the thermostat housing and the gauge would respond. Again if you have any ideas Let me know.

[WingAdmin]

How far does the needle move when you ground it out?

[Drdoom]

it is proportional the longer I ground it, the farther it goes. It will travel all the way.It retracts when ungrounded.

[Rambozo]

Measure the resistance of the sensor, when cold, and when hot. It's sounds like you got a bad new sensor. Rare, but it could happen. Also check the resistance of the plug to make sure it is making contact to the sensor.