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Permanent Fault, Signal Too Low






Permanent fault, signal too low

Checking connector








- Ignition off.
- Intake air temperature (IAT) sensor connector disconnected.
Connect an ohmmeter between intake air temperature (IAT) sensor connector terminal 1 (to control module) and ground.





The ohmmeter should display 3,000-4,500 ohms.

OK - Defective intake air temperature (IAT) sensor

Not OK - Checking cable

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Defective intake air temperature (IAT) sensor
Try a new intake air temperature (IAT) sensor according to Replacing the intake air temperature sensor Replacing The Intake Air Temperature Sensor.

Continue - Verification

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Checking cable
Check cable between intake air temperature (IAT) sensor connector terminal 1 and engine control module (ECM) terminal 48 for a short-circuit to ground according to Checking wiring and terminals. Permanent fault Checking Wiring And Terminals. Permanent Fault.
Remedy as necessary.





Continue - Verification

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Verification








- Reconnect connectors, reinstall components.
- Connect the VCT 2000.
- Ignition on.
Read the parameter AIR TEMP.





Is this reading OK?

Yes - FAULT FOUND

No - No Fault Found 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 - Exit fault-tracing

No - Attempt New Test

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Attempt New Test - Checking connector

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