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Diagnostic Trouble Code (DTC) Information






Diagnostic trouble code (DTC) information ECM-1200

Condition




Diagnostic trouble code (DTC) ECM-1200 is stored if the engine has been running for 3 minutes and been idling for at least 60 seconds and the control module receives a signal from the intake air temperature sensor (integrated in the mass air flow (MAF) sensor) corresponding to a temperature lower than -29 °C or higher than +129 °C The diagnostic trouble code (DTC) is also stored if the signal is not plausible for the intake air temperature sensor for a certain period of time.

Substitute value
+20 °C.
Three-way catalytic converter (TWC) preheating and idle air trim diagnostics are disabled.

Possible source

Signal too high:
- Short-circuit to ground in the signal cable
- Defective intake air temperature (IAT) sensor.

Signal too low:
- Contact resistance or oxidation in the terminals
- Open-circuit in the signal cable
- Open-circuit in the signal ground cable
- Short-circuit to supply voltage in the signal cable
- Defective intake air temperature (IAT) sensor.

Faulty signal:
- Contact resistance or oxidation in the terminals
- Defective intake air temperature (IAT) sensor.

Fault symptom[s]
- Malfunction indicator lamp (MIL) lit
- Poor performance.