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RZNT4R · 09-07-2021, 04:56 PM

If you car is throwing a code with the ignition in the accessory position you've got a whole other set of problems than a temp sensor dtc.

Do you perhaps mean ON, as in Key On Engine Off? Is the dash on and the check engine light illuminated? Is the temp needle moving? Yes? You're in ON, not accessory.

Anyway, it's a 2 wire circuit from and back to the ECM with an open circuit code, it doesn't get any easier to diag than this. Key ON, temp sens disconnected, you've got 5V on one wire (terminal 2) and ground on the other (terminal 1) if either is missing, check for it at the ECM (connector A36, terminals 29 and 30). If one is missing backprobing the ECM connector then the issue is in the connector (check for terminal tension, defective wire crimps or bent pins) or in the ECM, if both are present at the ECM then your issue is in the harness, find where the wire is cut, if both are present at the temp sensor then your issue is in the connector or the temp sensor, but you've thrown one at it already lol, in this case check for appropriate tension in the terminals, defective wire crimps and bent pins again.

09-07-2021, 04:56 PM	#3
RZNT4R Professional Mechanic Join Date: Apr 2010 Drives: 2017 86 6MT Oceanic Location: Quebec, Canada Posts: 789 Thanks: 17 Thanked 634 Times in 371 Posts Mentioned: 12 Post(s) Tagged: 0 Thread(s)	If you car is throwing a code with the ignition in the accessory position you've got a whole other set of problems than a temp sensor dtc. Do you perhaps mean ON, as in Key On Engine Off? Is the dash on and the check engine light illuminated? Is the temp needle moving? Yes? You're in ON, not accessory. Anyway, it's a 2 wire circuit from and back to the ECM with an open circuit code, it doesn't get any easier to diag than this. Key ON, temp sens disconnected, you've got 5V on one wire (terminal 2) and ground on the other (terminal 1) if either is missing, check for it at the ECM (connector A36, terminals 29 and 30). If one is missing backprobing the ECM connector then the issue is in the connector (check for terminal tension, defective wire crimps or bent pins) or in the ECM, if both are present at the ECM then your issue is in the harness, find where the wire is cut, if both are present at the temp sensor then your issue is in the connector or the temp sensor, but you've thrown one at it already lol, in this case check for appropriate tension in the terminals, defective wire crimps and bent pins again. Last edited by RZNT4R; 09-07-2021 at 06:14 PM.