Circuit Description
The barometric pressure (BARO) sensor is installed in the engine control module (ECM).
If the ECM detects a signal voltage that is excessively low or high, DTC 0071 will be set.
Conditions for Setting the DTC
The BARO sensor voltage exceeding 4.7 volts or lower than 1.9 volts and conditions are met for more than 1 second.
Action Taken When the DTC Sets
Based on the atmospheric pressure of 100 kPa (14.5 psi).
Conditions for Clearing the MIL/DTC
| • | The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail. |
| • | A current DTC, Last Test Failed, clears when the diagnostic runs and passes. |
| • | A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic. |
| • | Clear the MIL and the DTC with a scan tool. |
DTC 0071 can be cleared by using the Clear Info on the scan tool or by using the Diag Clear Switch.
Diagnostic Aids
Inspect for the following conditions:
| • | Poor connection at the ECM |
| Inspect the harness connectors for backed-out terminals, improper mating, broken locks, improperly formed or damaged terminals, and poor terminal-to-wire connection. |
| • | Damaged harness |
| Inspect the wiring harness for damage, shorts to ground, shorts to battery, and open circuits. If the harness appears to be OK, observe the display on the scan tool while moving connectors and wiring harnesses related to the BARO sensor. A change in the BARO scan tool display will indicate the location of the fault. |
Step | Action | Yes | No |
|---|---|---|---|
Schematic Reference: Engine Controls Schematics | |||
1 | Does DTC 0071 set while the ignition is ON and the engine is running? | Go to Step 2 | Go to Diagnostic Aids |
2 | Clear the DTCs. Does DTC 0071 reset? | Go to Step 3 | System OK |
3 | Replace the ECM. Refer to Engine Control Module Replacement/Restore Fuel Rate Data . Did you complete the replacement? | Go to Step 4 | -- |
4 | Clear the DTCs. Does DTC 0071 reset? | Go to Step 2 | System OK |
