| Table 1: | Normal Value - When VCC = 5V |
| Table 2: | Guide Line Value - When BARO = 100 kPa |
Circuit Description
The boost pressure sensor is located on the intake manifold and is connected to the intake manifold by a vacuum hose.
The boost pressure sensor generates a voltage according to air pressure and the generated voltage is input to the engine control module (ECM) for boost pressure sensor signal.
If the ECM detects a boost pressure sensor signal voltage that is excessively low this DTC will set.
Conditions for Running the DTC
| • | DTCs P0237 and P0238 are not set. |
| • | The engine is running. |
| • | The accelerator is open more than 80 percent. |
| • | The actual boost pressure is normal. |
Conditions for Setting the DTC
| • | The ECM detects a low boost pressure. |
| • | The conditions are met for 25 seconds or more. |
Action Taken When the DTC Sets
| • | The control module stores the DTC information into memory when the diagnostic runs and fails. |
| • | The malfunction indicator lamp (MIL) will illuminate. |
Conditions for Clearing the DTC
| • | A current DTC Last Test Failed clears when the diagnostic runs and passes. |
| • | Clear the DTC with a scan tool. |
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 boost pressure display on the scan tool while moving connectors and wiring harnesses related to the boost pressure sensor. A change in the scan tool display will indicate the location of the fault. |
| • | Lack of engine power. |
Boost Pressure | Sensor Voltage |
67 kPa (9.7 psi) | About 0.5 V Negative pressure |
200 kPa (29 psi) | 2.5 V |
333 kPa (48 psi) | 4.5 V |
Voltage | 2 V or less |
Boost Pressure | 70 kPa (10 psi) or less |
CKP | 2,000 RPM |
Acceleration | 100% |
Step | Action | Yes | No |
|---|---|---|---|
Schematic Reference: Engine Controls Schematics | |||
1 | Does the DTC set while the ignition is ON and the engine is running? | Go to Step 2 | Go to Intermittent Conditions |
2 |
Important: Other boost codes could set when performing this operation. Does the voltage indicate normal value according to boost table? | Go to Step 3 | Go to Step 8 |
3 | When boost pressure applied, is wastegate pressure normal? | Go to Step 4 | Go to Step 9 |
4 | Inspect the turbocharger and ducting for leakage or other abnormalities. Did you find and correct the condition? | Go to Step 13 | Go to Step 5 |
5 | Drive the vehicle and observe the boost sensor with a scan tool. Refer to Guide Line Value - When BARO = 100 kPa table. Does the actual boost pressure and voltage indicate guide line value at 80 percent acceleration or more? | Go to Step 6 | Go to Step 10 |
6 | Are any other DTCs set? | Go to Step 11 | Go to Step 7 |
7 | Clear the DTCs. Does the DTC reset? | Go to Step 12 | Go to Step 13 |
8 |
Important: The actual output voltage of boost sensor will be affected if the supply voltage to the sensor is changed. Replace the boost pressure sensor or repair/replace boost pressure sensor wiring harness. Did you complete the action? | Go to Step 13 | -- |
9 | Repair the wastegate. Did you complete the repair? | Go to Step 13 | -- |
10 | Replace the boost pressure sensor and/or repair the turbocharger. Did you complete the action? | Go to Step 13 | -- |
11 | Repair other DTCs first. Did you complete the repair? | Go to Step 13 | -- |
12 | Replace the ECM. Did you complete the replacement? | Go to Step 13 | -- |
13 | Clear the DTCs. Does the DTC still set? | Go to Step 2 | Go to Step 14 |
14 | Do any other DTCs set? | System OK | |
