P0238

P0238-MAP SENSOR VOLTAGE TOO HIGH





For complete wiring diagrams refer to Diagrams/Electrical.


- When Monitored:

With the ignition on and battery voltage greater than 10.4 volts.

- Set Condition:

The circuit voltage to the ECM is above a calibrated threshold for a certain period of time.







Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding.

Diagnostic Test


1. OTHER DTCS

Turn the ignition on.

With the scan tool, read the Engine DTCs.

Is there a 5-volt Supply DTC set?

Yes

- Refer to symptom list for problems related to the 5-volt Supply DTC.
- Perform POWERTRAIN VERIFICATION TEST. Powertrain Verification Test

No

- Go To 2

2. HIGH VOLTAGE





Turn the ignition off.

Disconnect the Map sensor harness connector.

Check connectors - Clean/repair as necessary.

Turn the ignition on.

Measure the voltage between the (F855) 5-volt supply circuit and (K916) Sensor Return circuit of the Map sensor harness connector.

Is the voltage between 4.5 and 5.5 volts?

Yes

- Go To 3

No

- Go To 4

3. MAP SENSOR





While monitoring scan tool, use a jumper wire to connect the (K916) Return circuit with the (K37) MAP Signal circuit at the sensor connector.

Did the P0237-MAP SENSOR VOLTAGE TOO LOW, DTC set?

Yes

- Go To 4

No

- Replace the MAP sensor.
- Perform POWERTRAIN VERIFICATION TEST. Powertrain Verification Test

4. (K37) MAP SIGNAL CIRCUIT SHORTED TO BATTERY





Disconnect the ECM harness connectors.

Check connectors - Clean/repair as necessary.

Measure the voltage between the (K37) MAP Signal circuit at the MAP Sensor harness connector and Battery Negative.

Is the voltage greater than 1 volt?

Yes

- Repair (K37) MAP Signal circuit shorted to Battery or replace harness.
- Perform POWERTRAIN VERIFICATION TEST. Powertrain Verification Test

No

- Go To 5

5. (F855) 5-VOLT SUPPLY CIRCUIT SHORTED TO BATTERY





Measure the voltage between the (F855) 5-volt supply circuit at the MAP sensor harness connector and Battery negative.

Is the voltage greater than 1 volt?

Yes

- Repair the (F855) 5-volt supply circuit shorted to Battery or replace harness.
- Perform POWERTRAIN VERIFICATION TEST. Powertrain Verification Test

No

- Go To 6

6. (K37) MAP SIGNAL CIRCUIT SHORT TO 5-VOLT SUPPLY





Turn the ignition off.

Disconnect the ECM harness connectors.

Measure the resistance between the (K37) MAP Signal circuit of the sensor harness connector and the (F855) 5-volt Supply circuit of the sensor harness connector.

Is the resistance less than 10 Ohms?

No

- Go To 7

Yes

- Repair or replace the engine harness.
- Perform POWERTRAIN VERIFICATION TEST. Powertrain Verification Test

7. (K916) SENSOR RETURN CIRCUIT OPEN





Measure the resistance between the (K916) Sensor Return circuit in the Map sensor harness connector with the (K916) Sensor Return circuit in the ECM harness connector.

Is the resistance less than 10 Ohms?

Yes

- Go To 8

No

- Repair or replace the engine harness.
- Perform POWERTRAIN VERIFICATION TEST. Powertrain Verification Test

8. INTERMITTENT CONDITION





Reconnect the ECM harness connector.

Turn the ignition on.

While monitoring scan tool, connect a jumper wire between the (K37) MAP Signal circuit of the sensor harness connector and the (K916) Return circuit of the sensor harness connector.

Does the scan tool show P0237-MAP SENSOR VOLTAGE TOO LOW DTC?

Yes

- Refer to the INTERMITTENT CONDITION Diagnostic Procedure. Intermittent Condition
- Refer to Engine / Testing and Inspection.

No

- Replace and program the ECM.
- Perform POWERTRAIN VERIFICATION TEST. Powertrain Verification Test