GL 1500 Change the coolant temperature sensor
- jaimemu
- Posts: 26
- Joined: Tue Jun 24, 2014 2:44 am
- Location: San Sebastian, Pais Vasco, Spain
- Motorcycle: GL 1500 1988
GL 1500 Change the coolant temperature sensor
The temperature display doesn't work properly. I will want to change the temperature gauge, (coolant temperature sensor).
I read some post about the procedure for to change the gauge, (Remove the Tupperware, fans and radiators), and finally I can see the body for thermostat and gauge, but as many user said is too difficult to work in the small environment.
I see the next picture, corresponds to what I can see, and the manual drawing.
In the photo I see a green plastic with a wire element.
The question are; how do I take off the hood? I don't want to break something that can be complicated, you fix it in that small space Thanks for your help
Jaime (from Spain)
I read some post about the procedure for to change the gauge, (Remove the Tupperware, fans and radiators), and finally I can see the body for thermostat and gauge, but as many user said is too difficult to work in the small environment.
I see the next picture, corresponds to what I can see, and the manual drawing.
In the photo I see a green plastic with a wire element.
The question are; how do I take off the hood? I don't want to break something that can be complicated, you fix it in that small space Thanks for your help
Jaime (from Spain)
- Elmobile
- Posts: 256
- Joined: Sat Aug 22, 2015 8:35 pm
- Location: Bridgewater, Nova Scotia, Canada
- Motorcycle: 1990 GL1500SE
Re: GL 1500 Change the coolant temperature sensor
The temperature sensor for the gauge is not the one of your pics... This one feeds the ECU.
The one for the gauge is located on the bottom of the left radiator... Easy access. lot easier than the one you are wanted to remove.
The one for the gauge is located on the bottom of the left radiator... Easy access. lot easier than the one you are wanted to remove.
- Elmobile
- Posts: 256
- Joined: Sat Aug 22, 2015 8:35 pm
- Location: Bridgewater, Nova Scotia, Canada
- Motorcycle: 1990 GL1500SE
Re: GL 1500 Change the coolant temperature sensor
Correction: My mistake...
The sensor you pointed at is the one for the gauge. The one on the right manifold is the engine temperature sensor feeding the ECU. The one on the radiator is the thermostatic switch for the fans...
To remove the connector, there is a little tab on the top which needs to be push down to unlatch it. Then you gently pull it out. They do come easy when correctly unlatch. Getting to it was not easy when I had to replace a leaky thermostat seal...

The sensor you pointed at is the one for the gauge. The one on the right manifold is the engine temperature sensor feeding the ECU. The one on the radiator is the thermostatic switch for the fans...
To remove the connector, there is a little tab on the top which needs to be push down to unlatch it. Then you gently pull it out. They do come easy when correctly unlatch. Getting to it was not easy when I had to replace a leaky thermostat seal...
-
- Posts: 102
- Joined: Sat Jun 06, 2020 10:57 am
- Location: Kansas
- Motorcycle: 2000 GL1500SE
2007 ST1300A ABS
Re: GL 1500 Change the coolant temperature sensor
I had the same issue and just recently replaced the sensor in your picture. I accessed by removing the left cooling fan. There is a procedure in the service manual. Aside from being a little tedious the only issue I had was clearance with the housing for the throttle/cruise control cable. I removed the retaining bolts for that housing to gain access to the fan housing upper retuning bolts.jaimemu wrote: ↑Thu Sep 10, 2020 2:53 pm The temperature display doesn't work properly. I will want to change the temperature gauge, (coolant temperature sensor).
I read some post about the procedure for to change the gauge, (Remove the Tupperware, fans and radiators), and finally I can see the body for thermostat and gauge, but as many user said is too difficult to work in the small environment.
I see the next picture, corresponds to what I can see, and the manual drawing.
In the photo I see a green plastic with a wire element.
The question are; how do I take off the hood? I don't want to break something that can be complicated, you fix it in that small space
desmontar sensor temperatue.jpg
Thanks for your help
Jaime (from Spain)
- jaimemu
- Posts: 26
- Joined: Tue Jun 24, 2014 2:44 am
- Location: San Sebastian, Pais Vasco, Spain
- Motorcycle: GL 1500 1988
Re: GL 1500 Change the coolant temperature sensor
Hi. Thank you for your answers. When deepening, new doubts arise; In the manual HONDA GL 1500 1988-1992 (Service-repair maintenance) Cap 11 COOLING SYSTEM. the following references appear in the diagram for (1988-1989):
14.- Coolant temperature sensor
15.- Tw sensor As of 1990, item no. 15 "Tw sensor" no longer appears, and only the "coolant temp sensor" appears.
My question for the 1998 GL 1500, which of the 2 references (14 or 15) handles the temperature gauge?
According to the diagram in the same manual, it is the "coolant temp sensor" that connects with the temperature indicator.
But I'm not sure, since in the photo of the GW, I have located the green connector (see initial photo) What is the ref 15 "Tw sensor" for?
On the other hand, the sensor works by difference in resistance (ohms), which causes the temperature increase, the sensor in the scheme is derived to ground, so I am blocked
thanks, Jaime
14.- Coolant temperature sensor
15.- Tw sensor As of 1990, item no. 15 "Tw sensor" no longer appears, and only the "coolant temp sensor" appears.
My question for the 1998 GL 1500, which of the 2 references (14 or 15) handles the temperature gauge?
According to the diagram in the same manual, it is the "coolant temp sensor" that connects with the temperature indicator.
But I'm not sure, since in the photo of the GW, I have located the green connector (see initial photo) What is the ref 15 "Tw sensor" for?
On the other hand, the sensor works by difference in resistance (ohms), which causes the temperature increase, the sensor in the scheme is derived to ground, so I am blocked
thanks, Jaime
-
- Posts: 102
- Joined: Sat Jun 06, 2020 10:57 am
- Location: Kansas
- Motorcycle: 2000 GL1500SE
2007 ST1300A ABS
Re: GL 1500 Change the coolant temperature sensor
#14 is the sensor for the Temp Gauge on the Dash. It has a single green with blue stripe wire. If you unplug that wire and ground it with the key on the coolant temp meter should go full hot. That would verify the wiring is good and the sensor is bad. On the '98' model the WT sensor became the ECT (Engine Coolant Temperature sensor) #22 on the 98 parts diagram. I use www.ronayers.com for parts diagrams.
- jaimemu
- Posts: 26
- Joined: Tue Jun 24, 2014 2:44 am
- Location: San Sebastian, Pais Vasco, Spain
- Motorcycle: GL 1500 1988
Re: GL 1500 Change the coolant temperature sensor
Thanks Crusty1, today I was able to access the sensor and I have put the end of the wire to ground. The needle of the temperature gauge in the box has gone to "H".
The cables are OK and I will proceed to change the sensor and the O-ring as the manual says. Thanks
The cables are OK and I will proceed to change the sensor and the O-ring as the manual says. Thanks
-
- Posts: 102
- Joined: Sat Jun 06, 2020 10:57 am
- Location: Kansas
- Motorcycle: 2000 GL1500SE
2007 ST1300A ABS
Re: GL 1500 Change the coolant temperature sensor
Just FYI I believe the thread on the unit is a tapered pipe thread. Use some Teflon tape on it to help seal it. It needs to be tight maybe 6-8 ft lbs ( my guess) or so but don’t over tighten it as that can crack the housing or enlarge the hole. Test with an ohm meter after installing and don’t forget to clean the connector before plugging it in securely. Once you get to the point you can add coolant and start the engine run it long enough to verify the gauge is moving before buttoning up the Tupperware.
- jaimemu
- Posts: 26
- Joined: Tue Jun 24, 2014 2:44 am
- Location: San Sebastian, Pais Vasco, Spain
- Motorcycle: GL 1500 1988
Re: GL 1500 Change the coolant temperature sensor
thanks, I have the sensor in sight, also the spare part, it has the cylindrical thread.
Now I find myself in a problem (precisely not to break the case). It is very hard, I am using a 12mm wrench with an extension and I am afraid of the case. Although I have used MD-40 spray screw loosening
The assembly procedure in the manual indicates "Apply sealant Honda Silicone Liquid Gastet" to the temperature sensor threaded before install "
It may be that the hardness in unscrewing is due to the sealant.
Now I find myself in a problem (precisely not to break the case). It is very hard, I am using a 12mm wrench with an extension and I am afraid of the case. Although I have used MD-40 spray screw loosening
The assembly procedure in the manual indicates "Apply sealant Honda Silicone Liquid Gastet" to the temperature sensor threaded before install "
It may be that the hardness in unscrewing is due to the sealant.
- jaimemu
- Posts: 26
- Joined: Tue Jun 24, 2014 2:44 am
- Location: San Sebastian, Pais Vasco, Spain
- Motorcycle: GL 1500 1988
Re: GL 1500 Change the coolant temperature sensor
Finally I have been able to release the sensor and I am going to proceed with the mounting of all this.
I'll try to do a tut. about what I have had to do, and upload it for help from other WGs
end part one: disassembly "coolant temperature sensor"
I'll try to do a tut. about what I have had to do, and upload it for help from other WGs
end part one: disassembly "coolant temperature sensor"
- jaimemu
- Posts: 26
- Joined: Tue Jun 24, 2014 2:44 am
- Location: San Sebastian, Pais Vasco, Spain
- Motorcycle: GL 1500 1988
Re: GL 1500 Change the coolant temperature sensor
Mainly thanks a lot Crusty1, his help has been invaluable
- jaimemu
- Posts: 26
- Joined: Tue Jun 24, 2014 2:44 am
- Location: San Sebastian, Pais Vasco, Spain
- Motorcycle: GL 1500 1988
Re: GL 1500 Change the coolant temperature sensor
Sorry I'm confused, the unit thread is a tapered pipe thread