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 overheating condition may cause this DTC to set.
- After starting the engine, the ECT should rise steadily to about 90°C (194°F) then stabilize when the thermostat opens.
- Use the Temperature vs. Resistance table to test the ECT sensor at various temperature levels to evaluate the possibility of a skewed sensor. A skewed sensor could result in poor driveability concerns. Refer to Temperature vs Resistance .
- If the condition is suspected of being an intermittent, refer to Intermittent Conditions .
DTC P0117- ECT Sensor Circuit Low Voltage
| Step | Action | Values | 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 engine coolant temperature (ECT) sensor parameter with a scan tool. Is the ECT sensor parameter more than the specified value? |
138°C (280°F) | Go to Step 4 | Go to Step 3 |
| 3 |
|
- | Go to Step 4 | Go to Diagnostic Aids |
| 4 |
|
-38°C (-36°F) | Go to Step 6 | Go to Step 5 |
| 5 | Test the signal circuit of the ECT sensor for a short to ground or a short to the ECT low reference circuit. Refer to Circuit Testing
and Wiring Repairs
in Wiring Systems. Did you find and correct the condition? |
- | Go to Step 10 | Go to Step 8 |
| 6 | Test for an intermittent and for a poor connection at the ECT sensor. Refer to Testing for Intermittent Conditions and Poor Connections
and Connector Repairs
in Wiring Systems. Did you find and correct the condition? |
- | Go to Step 10 | Go to Step 7 |
| 7 | Replace the ECT sensor. Refer to Engine Coolant Temperature (ECT) Sensor Replacement
. Did you complete the replacement? |
- | Go to Step 10 | - |
| 8 | Test for an intermittent and for a poor connection at the powertrain control module (PCM). Refer to Testing for Intermittent Conditions and Poor Connections
and Connector Repairs
in Wiring Systems. Did you find and correct the condition? |
- | Go to Step 10 | Go to Step 9 |
| 9 | Replace the PCM. Refer to Powertrain Control Module (PCM) Replacement
. Did you complete the replacement? |
- | Go to Step 10 | - |
| 10 |
|
- | Go to Step 2 | Go to Step 11 |
| 11 | 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 |