Diagnostic Aids
WARNING: This page is about a different car, the 2004 Buick Regal. However, it is still accessible from the selected car via links, so may be relevant.
- When the vehicle is at ambient temperature, the IAT sensor and the engine coolant temperature (ECT) sensor temperatures should be relatively close to each other. Refer to Temperature vs Resistance .
- If an intermittent condition is suspected, refer to Intermittent Conditions .
DTC P0112
| Step | Action | Values | Yes | No |
|---|---|---|---|---|
| Schematic Reference: Engine Controls Schematics Connector End View Reference: Engine Controls Connector End Views or Powertrain Control Module (PCM) 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 intake air temperature (IAT) sensor parameter with a scan tool. Is the IAT sensor parameter more than the specified value? |
123°C (253°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 IAT sensor for a short to ground or a short to the IAT low reference circuit and repair as necessary. 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 IAT 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 IAT sensor. Refer to Intake Air Temperature (IAT) 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 |