Monday, September 21st, 2020 AT 1:48 PM
JEBBANKS
- MEMBER
- 2016 CADILLAC CTS
- 3.6L
- 6 CYL
- AUTOMATIC
- 40,900 MILES
Temp sensor failure.
Temperature sensor not working
8 Replies
JEBBANKS
- MEMBER
- 5 POSTS
Sorry, some more detail.
I think one or both temperature sensors failed. Arm on gauge doesn’t move from bottom position once underway. Fans run at all times. Car runs rough. Having trouble locating the sensors.
Any help is appreciated. Thanks!
I think one or both temperature sensors failed. Arm on gauge doesn’t move from bottom position once underway. Fans run at all times. Car runs rough. Having trouble locating the sensors.
Any help is appreciated. Thanks!
SPONSORED LINKS
Was this helpful?
Yes
No
Monday, September 21st, 2020 AT 3:14 PM
KASEKENNY
- MECHANIC
- 18,907 POSTS
I attached the replacement process for this component. Let me know if you need other information like if you have a code. If you do, I would suggest we run through the testing rather then just replacing it as there could be other issues.
Image (Click to make bigger)
Was this helpful?
Yes
No
Monday, September 21st, 2020 AT 3:16 PM
KASEKENNY
- MECHANIC
- 18,907 POSTS
Just saw your update. Do you have any codes?
https://www.2carpros.com/articles/checking-a-service-engine-soon-or-check-engine-light-on-or-flashing
If the gauge is the only thing not working then it could be just a sensor or it could be a wiring issue or cluster issue.
Let's cover this and then figure out next steps.
https://www.2carpros.com/articles/checking-a-service-engine-soon-or-check-engine-light-on-or-flashing
If the gauge is the only thing not working then it could be just a sensor or it could be a wiring issue or cluster issue.
Let's cover this and then figure out next steps.
Was this helpful?
Yes
No
Monday, September 21st, 2020 AT 3:18 PM
JEBBANKS
- MEMBER
- 5 POSTS
I don’t have any codes. I also looked at the coolant tank and it looked low. Could that be causing this?
Was this helpful?
Yes
No
Monday, September 21st, 2020 AT 5:05 PM
JEBBANKS
- MEMBER
- 5 POSTS
Does this engine have two sensors?
SPONSORED LINKS
Was this helpful?
Yes
No
Monday, September 21st, 2020 AT 5:15 PM
KASEKENNY
- MECHANIC
- 18,907 POSTS
I am only showing one sensor. I attached the way this works. If the needle for the coolant temp in the cluster is not working then this is one of a couple things.
Basically the cluster displays temp that it gets from the BCM. The BCM gets the data from the PCM where the PCM reads it from the sensor.
The fact that you have no codes points to a cluster issue. If the BCM or PCM was not getting the correct signal it would set a code.
The way to tell this, is to hook up a scan tool and look in the PCM and BCM and see if there is an engine coolant temp. If there is nothing then it is not getting the signal. The other possible reading would be -40 degrees. If they are reading this, then the sensor is the issue. -40 degrees basically says the sensor is and open circuit and the cluster will try to display this by putting the needle as far down as it can go and it doesn't move.
Basically the cluster displays temp that it gets from the BCM. The BCM gets the data from the PCM where the PCM reads it from the sensor.
The fact that you have no codes points to a cluster issue. If the BCM or PCM was not getting the correct signal it would set a code.
The way to tell this, is to hook up a scan tool and look in the PCM and BCM and see if there is an engine coolant temp. If there is nothing then it is not getting the signal. The other possible reading would be -40 degrees. If they are reading this, then the sensor is the issue. -40 degrees basically says the sensor is and open circuit and the cluster will try to display this by putting the needle as far down as it can go and it doesn't move.
Image (Click to make bigger)
Was this helpful?
Yes
No
Monday, September 21st, 2020 AT 6:52 PM
JEBBANKS
- MEMBER
- 5 POSTS
Thanks so much for this. I don’t have a code reader. That’s why I have no codes. Will try to get one. Every auto part store I called said there are two sensors; one that is similar in shape to a spark plug and one that is more of a 90 degree angle. They all said one is on the block and the other is in the coolant line? I bought both figuring it has to be one of them. Locating them is where I’m having a problem. Can’t find location anywhere online. In the first diagram you sent, where is that on the engine? Also, coolant appears to be low. Could that be a contributor to no temperature reading?
Was this helpful?
Yes
No
Tuesday, September 22nd, 2020 AT 4:17 AM
KASEKENNY
- MECHANIC
- 18,907 POSTS
No. Low coolant will not effect the temperature gauge. Can you get a picture of the parts and part numbers that they gave you? I suspect they are confusing something else as a coolant temperature sensor. The temperature sensor that I am showing you is what is used by the PCM to determine engine temperature. Then the PCM sends this info to the BCM which then sends it to the cluster to display it.
As for the location of what I sent. That is on the top of the engine under the fuel injector noise shield towards the front of the motor.
I attached more info on what needs to come out to replace this.
As for the location of what I sent. That is on the top of the engine under the fuel injector noise shield towards the front of the motor.
I attached more info on what needs to come out to replace this.
Images (Click to make bigger)
Was this helpful?
Yes
No
Tuesday, September 22nd, 2020 AT 6:40 PM
