ECM code 15
Thread Starter
Cruising
Joined: Nov 2012
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ECM code 15
I now have a "service engine soon" light - I checked the ECM code which returned 15 - coolant sensor temp. I recently replaced the coolant sensor temp gauge and have driven a little over 50 miles with no problems, now suddenly the error code started. The connections on the sensor look fine. Not long ago I installed a 160 degree thermostat, could that have something to do with it? Also, when I reset the system, it keeps giving me the error...what should I do next? Thanks for your help.
Safety Car
Joined: Jan 2004
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Code 15 Low coolant TEMP indicated; not the coolant level
A CTS fault
http://www.chevythunder.com/cts_diagnostic_pg2.htm
The partner to Code 14 ; high coolant temp indicated
There is no connection to the ECM or a error code for the low coolant LEVEL sensor you speak of
A CTS fault
http://www.chevythunder.com/cts_diagnostic_pg2.htm
The partner to Code 14 ; high coolant temp indicated
There is no connection to the ECM or a error code for the low coolant LEVEL sensor you speak of
Le Mans Master
Joined: Aug 2007
Posts: 8,735
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From: WV
Here's what the code indicates...WW
14 Check wiring, connectors, thermostat. Monitor actual engine temperature. If within limits, and wiring/connector is OK, change thermostat and/or sensor.
15 Coolant Sensor Circuit (Low)..See above, particularly thermostat
14 Check wiring, connectors, thermostat. Monitor actual engine temperature. If within limits, and wiring/connector is OK, change thermostat and/or sensor.
15 Coolant Sensor Circuit (Low)..See above, particularly thermostat
Last edited by WW7; Apr 14, 2013 at 10:15 PM.
Safety Car
Joined: Apr 2011
Posts: 3,660
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Code 15 Low coolant TEMP indicated; not the coolant level
A CTS fault
http://www.chevythunder.com/cts_diagnostic_pg2.htm
The partner to Code 14 ; high coolant temp indicated
There is no connection to the ECM or a error code for the low coolant LEVEL sensor you speak of
A CTS fault
http://www.chevythunder.com/cts_diagnostic_pg2.htm
The partner to Code 14 ; high coolant temp indicated
There is no connection to the ECM or a error code for the low coolant LEVEL sensor you speak of
I misread something. I thought it said low sensor....when it actually says "low resistence"...in sensor.
14 & 15 are partners in the coolant sensor circuit health...one is to show an open or break in the circuit the other indicates its shorted...easy enough to diagnose with that.
Thread Starter
Cruising
Joined: Nov 2012
Posts: 14
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Ok, so if I understand correctly, because I installed a 160 degree thermostat, the system is sensing this as a problem? All of the connections are fine as far as I can see. After I installed the new thermostat, it has been running cooler...under the 220 it typically ran before. Obviously I don't want to do any long term damage...Thanks for your help.
Safety Car
Joined: Apr 2011
Posts: 3,660
Likes: 22
Ok, so if I understand correctly, because I installed a 160 degree thermostat, the system is sensing this as a problem? All of the connections are fine as far as I can see. After I installed the new thermostat, it has been running cooler...under the 220 it typically ran before. Obviously I don't want to do any long term damage...Thanks for your help.
Not at all.
The engine will see temps lower than that every day.
You are not reading the description right...
its indicating that the wire is either shorted OR grounded somewhere. Code 14 or 15. These codes show the circult health, NOT the sensors working range. Everybody has a 160 stat....nobody else has a code 15.
Its a wire problem.
Go thru your grounds, separate your harness and inspect it. trace the wire to its source. Might need to be replaced. C4 wire is fragile and prone to insulation hardening and coming apart.
Another way of reading that code is low temp, which is the same as an open circuit? or high resistence..I forget which. The actual temp is not the issue according to the code list...its a signal that its reading a resistence thats lower than it should be for what is going on with the engine...more than likely a wire issue or connection somewhere. Possibly a sensor at fault. It happens. Is that the correct sensor for that location?
Last edited by leesvet; Apr 14, 2013 at 10:22 PM.
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Safety Car
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Posts: 3,556
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Given the age of these cars, consider replacing the CTS as periodic maintenance ( at $14 )
http://tpiparts.net/inc/sdetail/10956/497
The link I posted above has the FSM flowchart to follow in order to determine the fault
Last edited by vetteoz; Apr 15, 2013 at 01:15 AM.
Drifting
Joined: Feb 2013
Posts: 1,451
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poor running and hesitation
I have power at the connector in the blue and red wire. Then when the coolant hits 205, the fan switch temperature, the fuse blows.
The blue wire goes from the connector into the dash.
I thought that if I grounded the switch wire the fan would run. but it does not run. Any ideas? sorry for the long post
Safety Car
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Posted above
http://forums.corvetteforum.com/1583639262-post3.html
You are supposed to read all the previous posts before writing to a thread
not just tack a question on at the end.
Your question may have already been answered
Race Director
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From: Anaheim CA
The search feature is set up such that it searches on each word you enter and then shows all the results.
For example, if you search on "stall speed", it will show all the results for "stall" plus all the results for "speed". You end up with a zillion results. Try searching on a single word. That can be difficult... ;-)
You're better off searching Google for "Corvette Forum" plus your search terms. There are a lot more options for search terms.
For example, if you search on "stall speed", it will show all the results for "stall" plus all the results for "speed". You end up with a zillion results. Try searching on a single word. That can be difficult... ;-)
You're better off searching Google for "Corvette Forum" plus your search terms. There are a lot more options for search terms.
Drifting
Joined: Feb 2013
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The search feature is set up such that it searches on each word you enter and then shows all the results.
For example, if you search on "stall speed", it will show all the results for "stall" plus all the results for "speed". You end up with a zillion results. Try searching on a single word. That can be difficult... ;-)
You're better off searching Google for "Corvette Forum" plus your search terms. There are a lot more options for search terms.
For example, if you search on "stall speed", it will show all the results for "stall" plus all the results for "speed". You end up with a zillion results. Try searching on a single word. That can be difficult... ;-)
You're better off searching Google for "Corvette Forum" plus your search terms. There are a lot more options for search terms.