Signal Too Low. Permanent Fault

Signal too low. Permanent fault

Checking connector








- Ignition off.
- Check Mass Air Flow (MAF) sensor connector for contact resistance and oxidation according to Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault. The Intake Air Temperature (IAT) sensor is integrated into the Mass Air Flow (MAF) sensor.
- Reinstall components, reconnect connectors etc.
- Ignition on.
- Read off the intake air temperature (IAT).
If the temperature is now within its permitted range, the fault was caused by loose connections in the connector.

Other information
- To access/replace the Mass Air Flow (MAF) sensor, Service and Repair.













Is the signal OK?

Yes - FAULT FOUND

No - Checking wiring and components

-------------------------------------------------

Checking wiring and components
Check the Intake Air Temperature (IAT) sensor resistance between #1 and #3 on the Mass Air Flow (MAF) sensor. The Intake Air Temperature (IAT) sensor is integrated into the Mass Air Flow (MAF) sensor.

Note! The Intake Air Temperature (IAT) sensor can be defective if the signal cable has been short-circuited to supply voltage. Check this before replacing the sensor.

Check ground lead between control module #A5 (#A5) and Mass Air Flow (MAF) sensor connector #1 for an open-circuit according to Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault and a short-circuit to supply voltage according to Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault.

Hint: With the ignition on and the outside temperature sensor connector disconnected, the voltage between #1 and ground should be approximately 5 V.

Check ground lead between control module #A58 (#A58) and Mass Air Flow (MAF) sensor connector #3 for an open-circuit according to Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault.
Remedy as necessary.

Other information
- Connecting the breakout box/accessing the control module, see Connecting the breakout box, B5254T2 Connecting the Test Box.
- To access/replace the Mass Air Flow (MAF) sensor, Service and Repair.
- For resistance values, see Component specifications Specifications.
- For information about signals on 5-cylinder engines, see Signal specification Signal Specification.
- For information about signals on 6-cylinder engines, see Signal specification Signal Specification.













Continue - Verification

-------------------------------------------------

Verification




Verification

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








- Ignition off.
- Reconnect the connectors, reinstall components etc.
- Ignition on.
- Read off Intake Air Temperature (IAT) sensor signal. The Intake Air Temperature (IAT) sensor is integrated into the Mass Air Flow (MAF) sensor.
Check that the signal is OK according to the table value:.





Is the signal OK?

Yes - Verification completed

No - Fault-tracing information

-------------------------------------------------

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 - Exit Fault-Tracing

No - Attempt New Test

------------------------

Attempt New Test - Checking connector

-------------------------------------------------