Code 15
Thread Starter
Instructor
Joined: Apr 2008
Posts: 240
Likes: 0
From: Peachtree City GA
Code 15
Anybody Ever have code 15, It said CTS, Coolant Tempature Senor temp Senor High voltage... Would this just mean the sensor needs to be replaced? Both of the fans come on as soon as I start the engine
Anybody?
Sorry I always just ask the question, if i knew more i would give feed back as well....
Anybody?
Sorry I always just ask the question, if i knew more i would give feed back as well....
Intermediate
Joined: Oct 2006
Posts: 39
Likes: 0
From: Mesa AZ
rte 203
The coolant temp sensor is a thermistor. When cold, a thermistor will have high resistance, therefore the ECM will see a high voltage (5v). As the sensor warms up, the resistance becomes less and therefore the voltage will drop. I do not know what year corvette you have (sounds like an LT: 2 fans). On mine (87), a normal engine operating temp should give me around 2.0 volts. An open circuit or faulty connection can cause a code 15.
John
The coolant temp sensor is a thermistor. When cold, a thermistor will have high resistance, therefore the ECM will see a high voltage (5v). As the sensor warms up, the resistance becomes less and therefore the voltage will drop. I do not know what year corvette you have (sounds like an LT: 2 fans). On mine (87), a normal engine operating temp should give me around 2.0 volts. An open circuit or faulty connection can cause a code 15.
John
Last edited by F18tinman; May 10, 2009 at 04:53 PM. Reason: correction
Thread Starter
Instructor
Joined: Apr 2008
Posts: 240
Likes: 0
From: Peachtree City GA
rte 203
The coolant temp sensor is a thermistor. When cold, a thermistor will have high resistance, therefore the ECM will see a high voltage (5v). As the sensor warms up, the resistance becomes less and therefore the voltage will drop. I do not know what year corvette you have (sounds like an LT: 2 fans). On mine (87), a normal engine operating temp should give me around 2.0 volts. An open circuit or faulty connection can cause a code 15.
John
The coolant temp sensor is a thermistor. When cold, a thermistor will have high resistance, therefore the ECM will see a high voltage (5v). As the sensor warms up, the resistance becomes less and therefore the voltage will drop. I do not know what year corvette you have (sounds like an LT: 2 fans). On mine (87), a normal engine operating temp should give me around 2.0 volts. An open circuit or faulty connection can cause a code 15.
John
My C4 is a 1985, I guess i will try replacing the Sensor.
Thanks For the Info
Intermediate
Joined: Oct 2006
Posts: 39
Likes: 0
From: Mesa AZ
See if this troubleshooting procedure helps.
http://members.shaw.ca/corvette86/Code%2015.pdf
Good luck,
John
http://members.shaw.ca/corvette86/Code%2015.pdf
Good luck,
John
Thread Starter
Instructor
Joined: Apr 2008
Posts: 240
Likes: 0
From: Peachtree City GA
is the coolant tem sensor in the head or on the front of the block? The picture in the Artical shows the coolant temp sensor having two prongs, I do have a connector in the front of the block that looks like this but I also have a coolant sensor in the side of the passanger head, I think some one put a cooling switch and harness on this car.
Intermediate
Joined: Oct 2006
Posts: 39
Likes: 0
From: Mesa AZ
Rte203
If I remember correctly, the coolant temp sensor is located on the front of the engine in the intake manifold under the AIR control diverter valve (almost centered on the front of the intake manifold). I am out of town and cannot run out and take a look. I hope this helps.
John
If I remember correctly, the coolant temp sensor is located on the front of the engine in the intake manifold under the AIR control diverter valve (almost centered on the front of the intake manifold). I am out of town and cannot run out and take a look. I hope this helps.
John
Team Owner
Joined: Jan 2003
Posts: 20,254
Likes: 221
From: Summerland B.C. Canada
is the coolant tem sensor in the head or on the front of the block? The picture in the Artical shows the coolant temp sensor having two prongs, I do have a connector in the front of the block that looks like this but I also have a coolant sensor in the side of the passanger head, I think some one put a cooling switch and harness on this car.
http://members.shaw.ca/corvette86/Co...0View%2086.pdf
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Thread Starter
Instructor
Joined: Apr 2008
Posts: 240
Likes: 0
From: Peachtree City GA
The CTS is on the front of intake, beside the cold start valve's thermal switch.
http://members.shaw.ca/corvette86/Co...0View%2086.pdf
http://members.shaw.ca/corvette86/Co...0View%2086.pdf
I think someone added a Coolant switch like MAMW Sells ( its mounted in the side of the head) The cooling fan would come on at 200 Degrees, which Is lower than stock, how will this effect my diagnosis
