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Faulty Signal






Faulty signal

Determining the status

Reading off Diagnostic trouble code (DTC) status ECM-100A
Note! When reading off the diagnostic trouble code (DTC) status, other stored diagnostic trouble codes (DTCs) and their status will be listed.

- Read off the diagnostic trouble code (DTC) status. Check the status of the relevant diagnostic trouble code (DTC).





Was the status of the relevant diagnostic trouble code (DTC) permanent?

Yes - Checking the connectors

No - Checking the connectors

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Checking the connectors
Check the pressure sensor connector for intermittent contact resistance and oxidation. See Checking wiring and terminals. Intermittent faults Checking Wiring and Terminals. Intermittent Faults.

Other information
- To locate the manifold absolute pressure (MAP) sensor, see Location of components Locations
- To access and replace the engine control module (ECM), see
- For information about signals see Signal specification Signal Description / Specification.






Continue - Fault-tracing information

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Fault-tracing information




Information

Fault-tracing information
If the fault is intermittent, do not verify fault-tracing if the fault does not recur.
It is possible to view the information again, or leave fault-tracing for this diagnostic trouble code (DTC).

Do you want to view the information again?

Yes - Attempt New Test

No - Fault Found

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Attempt New Test - Checking the connectors

FAULT FOUND - DONE

DONE - DONE

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Checking the connectors








- Ignition off
- Check the connector for the intake manifold pressure sensor for contact resistance and oxidation. See Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault
- Reinstall the components, reconnect the connectors etc.

Other information
- To locate the manifold absolute pressure (MAP) sensor, see Location of components Locations
- To access and replace the engine control module (ECM), see
- For information about signals see Signal specification Signal Description / Specification.





Has the fault been found and remedied?

Yes - Verification

No - Checking the pressure sensors

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Checking the pressure sensors








- Ignition on
- Read off both the pressure in the intake manifold and the atmospheric pressure
- Compare the read off values. The difference between these values must not be greater than 70 hPa.
If the difference between the read off pressure values is less than 70 hPa, the cause of the fault was loose connections in the connector.
If the difference is in excess of 70 hPa, check which of the sensors probably gave an incorrect value.

Other information
- To locate the pressure sensors, see Location of components Locations
- Normal atmospheric pressure is 1013 hPa.

Select an alternative
1. The difference between the read off pressure values is < 70 hPa
2. The atmospheric pressure sensor seems to be faulty
3. The manifold absolute pressure (MAP) sensor seems to be faulty.





Which alternative is correct?

1 - Checking the connectors

2 - Replacing the atmospheric pressure sensor

3 - Replacing the manifold absolute pressure (MAP) sensor

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Replacing the manifold absolute pressure (MAP) sensor
To locate the manifold absolute pressure (MAP) sensor, see Location of components Locations.
Remedy as necessary.

Other information
- For information about signals, see Signal specification Signal Description / Specification
- For the normal values for the manifold absolute pressure (MAP) sensor, see Air pressure sensor intake manifold (MAP) [1][2]Manifold Pressure/Vacuum Sensor.






Continue - Verification

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Replacing the atmospheric pressure sensor
Replace the engine control module (ECM). See the relevant service procedure.

Note! The atmospheric pressure sensor is built into the engine control module (ECM) and cannot be replaced separately.

Caution! New engine control modules (ECM) are supplied without software. The engine control module (ECM) must be programmed when it has been replaced.

Remedy as necessary.


Continue - Verification

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Verification

Hint: After carrying out the repair, check that the fault has been remedied.








- Ignition off
- Reinstall the connectors, components etc.
- Ignition on
- Read off the value for the manifold absolute pressure (MAP) sensor and the value for the atmospheric pressure sensor
- The difference between these values must not be greater than 70 hPa.





Is the difference between the pressure sensors less than 70hPa?

Yes - Fault Found

No - Fault-tracing information

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Fault-tracing information




Information

Fault-tracing information
The fault should have been detected and remedied. As this is not the case fault-tracing has failed.
Exit fault-tracing for this diagnostic trouble code (DTC) or make another attempt.

Do you want to exit fault-tracing?

Yes - FAULT-TRACING FAILED

No - Attempt New Test

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FAULT-TRACING FAILED - FAULT-TRACING FAILED

Attempt New Test - Determining the status

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