hi guys,,i have a 94 sc2 that is getting no 5 volt signal to the coolant temp sensor,,i have just replaced that sensor plus the crank sensor,,fuel psi is good plus my fuses and relays are all working ,,my question is what is my next step to figure out the cause of no voltage,,,thxs for the help..

 

The yellow wire is the "hot" lead for the engine coolant temp sensor (ECTS). It comes directly from terminal C12 on the Powertrain Control Module (PCM).

Normally, I suggest replacing the ECTS connector at the same time you replace the sensor itself (OEM parts only, please) ... costs a bit more for parts, but things tend to work properly the first time.

 

and he does mean OEM parts only. Meaning do not buy the etcs from PetesParts&PartySupplies.

DEALER ONLY for ETCS and Connector

 

ok point taken regarding the connector,,,i have checked the connector and im geting a 5 volt reference signal to the connector,,i did notice that the connector part of the sensor spins if you try to turn it,,i dont want to sound stupid but im assuming that since its a 2 wire connector, the sensor is broken right??please advise,,,thanks guys

 

Hi there, PaulEdgar --

Short answer here --> Yep, the sensor is broken. Might have happened when you (tried to) put the old connector on the new sensor. Anyhow, you need to make another trip back to your local Saturn-friendly DEALERSHIP, and purchase an OEM sensor and associated electrical connector. Make sure you get the sensor with the metal tip ...

 

ok thanks for the info oceanarcher,,,if this does not fix my issue,what would be my next step if the sensor n connector dont fix it..possible ecm?a broken ground from the ecm?

 

Confusious once said something about worrying and rocking chairs --> it gives you something to do, but accomplishes nothing. Get your new sensor and associated connector properly installed and hooked up, then we can discover whether we need to go looking for "what ifs" ..........

 

ok oceanarcher,i bought a factory sensor and pigtail and replaced it and now the car will start but,my coolant light comes on and the check eng light as well,it says its a code 14 which is a issue with the sensor...??? im at my whits end with this car,,,what should i look for or do next,,,thxs for your help..

 

Well, first thing I'd do at this point, is to carefully disconnect the ECTS connector.

Leave the engine shut off for the next couple of tests.

Using an ohmmeter with long leads, I'd measure BLACK wire from the ECTS connector back to the Powertrain Control Module, contact C3 (should read zero ohms, or very close to it).

Now, read the YELLOW wire from the ECTS connector back to the PCM, contact C12 (again, it should read zero ohms).

Now, read the ECTS itself from terminal to terminal (should be between 100 ohms and 3,000 ohms, depending on ambient temperature)

Please let me know what you find ................

 

ok well i measured the resistance in both those wires and both read zero and the new sensor i put in reads about 2000 ohms