U1990 Trouble Code

View U1990 obd/2 error code description and symptoms. U1990 engine photo

Engine Coolant Temperature (ECT) Circuit High Input Indicates the sensor signal is greater than Self-Test maximum. The ECT sensor maximum is 4.6 volts or -50 C (-58 F). Note on some vehicles that are not equipped with an ECT sensor, CHT can be used and can set this DTC. Open circuit in harness Sensor signal short to power Damaged PCM Improper harness connection Damaged sensor ECT V PID reading greater than 4.6 volts with key ON and engine OFF or during any engine operating mode indicates a hard fault.

One example of this would be when an automatic vehicle in placed in gear. To prevent the added drag from the torque converter and transmission from reducing the idling speed, the PCM will command the idle control valve to allow more air to enter the engine, while at the same time, adjusting the injector pulse width to inject more fuel to suit the increased amount of air. Note that the idle air control valve is closed by the PCM when the throttle plate is opened to prevent excess air from entering the engine.

U1990 Error Code Repair Process :

If your air bag passenger inflator circuit resistance low on squib check engine light is illuminated, it's best to take it in for diagnostic testing, which can feel like a hassle. Because while the lights vary in appearance from vehicle to vehicle, all have the same basic meaning: There's a problem with the car's emissions system. The on-board diagnostics system U1990 and engine control unit are in charge of monitoring a bunch of different air bag passenger inflator circuit resistance low on squib, and if they get a reading that's a little out of whack, up pops the check engine light.

U1990 is a kind of Network Trouble Code

U-code indicates that engine communication errors and shows lost communication with engine parts.U-Codes are fairly straight forward, given all of the articles and technical publications that have been written regarding these problematic codes. In most cases, it just comes down to identifying the module that isn't communicating with the other modules on the CAN bus line for whatever reason.

Common Causes of U1990

A common cause of code U1990 is the failure of Air Bag Passenger Inflator Circuit Resistance Low on Squib, but there are several other possible causes as well, such as ;

Engine Control Module (ECM)
Faulty spark plug (s)
Fuel pressure
Insufficient cylinders compression

U1990 code for all cars

You can view according U1990 DTC for your car model. We selected several models to see obd2 solutions click and view it.

+U1990 Ford Crown Victoria

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