Diagnostic Aids

WARNING: This page is about a different car, the 2004 GMC Envoy XUV, 2004 GMC Envoy XL, 2004 Chevrolet TrailBlazer, and 2004 Buick Rainier. However, it is still accessible from the selected car via links, so may be relevant.

An ECT sensor or PCM which is intermittently shorted, open, or skewed is possible, but very unlikely.
An intermittent open or a short to voltage in the ECT sensor signal circuit could result in DTC P1115 setting. Refer to Intermittent Conditions .
Use the Temperature vs. Resistance Value table to test the coolant sensor at various temperature levels to evaluate the possibility of a skewed sensor. A skewed sensor could result in poor driveability conditions. Refer to Temperature vs Resistance .

DTC P1115

Step	Action	Yes	No
Schematic Reference: Engine Controls Schematics Connector End View Reference: Powertrain Control Module (PCM) Connector End Views or Engine Controls Connector End Views
1	Did you perform the Diagnostic System Check-Engine Controls?	Go to Step 2	Go to Diagnostic System Check - Engine Controls
2	Observe the DTC information with a scan tool. Is DTC P0118 set?	Go to DTC P0118	Go to Step 3
3	Turn OFF the engine. Turn ON the ignition, with the engine OFF. Observe the engine coolant temperature (ECT) sensor parameter with a scan tool while moving the ECT sensor connector and the powertrain control module (PCM) connector. Refer to Inducing Intermittent Fault Conditions in Wiring Systems. Does the scan tool indicate an abrupt change in value?	Go to Step 6	Go to Step 4
4	Observe the ECT parameter with a scan tool while moving the wiring harness at the ECT sensor and the PCM. Refer to Inducing Intermittent Fault Conditions in Wiring Systems. Does the scan tool indicate an abrupt change in value?	Go to Step 7	Go to Step 5
5	Observe the Freeze Frame/Failure Records for this DTC. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records. Did the DTC fail this ignition?	Go to Step 2	System OK
6	Repair the ECT connector or the terminal as necessary. Refer to Connector Repairs in Wiring Systems. Did you complete the repair?	Go to Step 8	-
7	Repair the wiring harness or the wiring as necessary. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair?	Go to Step 8	-
8	Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records. Did the DTC fail this ignition?	Go to Step 2	Go to Step 9
9	Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed?	Go to Diagnostic Trouble Code (DTC) List	System OK