well ive had this stupid code 15, high temperature coolant or whatever and i bought a new coolant temperature sensor, a new coolant temperature sender, and checked my wires for a possible split or frayed wire. the problem is that when i put my keys in the ignition and crank it over, the stupid gauge pegs and i can simply touch the needle and it will read the correct temperature. when i turn the car off everything will seem fine, but when i go to crank it back over again the gauge will peg again. then a code 15 is thrown. my mpg is suffering, cold performance is totally lacking. the problem is that my car will never pass emissions like this and my tags are overdue. could it be a ground possibly? could it be something that i overlooked? all of this code 15 came after i installed my new manifold, thanks a million for any help!

------------------
1987 LG4 Camaro z28
Modifications- Flowmaster 80 series, KN airfilter, high flow cat, 180* stat, edelbrock performer intake manifold, msd blaster coil, ascd big block hood, panasonic cd player, rockford everything else.

 

code 15 is Low temp. indicated right? unless my book is wrong, plz tell me just in case


do this:
Clear the codes,
Disconnect coolant sensor connector,
Jump Harness Terminals Together
Run engine for about 1 minute.
no turn the engine off, and ground the Diag. Terminal,
if u get a code 14: u have a faulty coolant sensor connection..
if u get code 15: clear codes, and have ignition off, probe the harness (i think its the yellow wire) with a voltmeter, the other lead to ground, u should get 4-6 volts, if not then ur ECM or wiring is faulty

if u get 4-6 volts, then the sensor ground circuit is open or you u have a faulty ECM connection or ECM.

anyone wanna add or change anything plz do.

------------------
- David
88' GTA 5.7L TPI MODS---> air foil, K&N, Shift Kit, 180* therm, TB bypass, Gutted CAT, Flowmaster 80 Series

http://www.geocities.com/david_angel_16

[This message has been edited by breathment (edited October 29, 2001).]

 

Twink,

The CTS used for the ECM is different than the sensor used to signal the dash instrument. The CTS that is causing the DTC 15 should have a yellow and a black wire connected to it, and should be located at the front of the intake manifold coolant crossover. The sensor for the gauge is probably in the left (possibly right on an LG4) cylinder head opening and has a single dark green wire.

The dash gauge is apparently having a problem with mechanical binding, but won't affect the CTS reading by the ECM. That is a strange coincidence, though.

The DTC 15 indicates an impossibly low reading from the CTS, and that usually means a failed sensor or open circuit (poor connection) on the yellow wire to the sensor. The black wire is a signal ground, but still needs to be connected to the sensor for a ground reference. Shorting the sensor yellow wire to ground should cause a DTC 14 - an impossibly high temperature reading.

Good luck with the dash gauge. I'm not sure what you can do about that short of removing the cluster and repairing the gauge.

------------------
Later,
Vader
------------------
If you want to beat the World, it might reach up and pull you down...
Adobe Acrobat Reader