U1679 Diagnostic Trouble Code

U1679 is a kind of OBD-II Diagnostic U-Network Diagnostic Trouble Code.

It is considered generic because it applies to all makes and models of vehicles, although specific repair steps may be different depending on your car model.

Symptoms

Symptoms of a U1679 diagnostic trouble code may include:

Lack of power
Faulty O2 Sensor
Poor acceleration
Hesitation upon acceleration

Possible Causes :

Some aftermarket accessories and performance modifications
A faulty oxygen sensor. This will set a code in itself, however, a faulty oxygen sensor does not automatically condemn the sensor. The code just means that the sensor signal was not within specifications. An air leak or any of the above will cause an erroneous signal. There is a multitude of O2 codes relating to O2 performance which gives a clue to the problematic area.
Rough running engine due to misfiring plugs. Many engines have misfire codes to indicate the cylinder effected, such as P0307 for number 7.

Repair Processes :

With the valve disconnected, the red voltmeter lead should be attached to the IMRC valve power wire and the black voltmeter lead connected to ground. Once located, visually inspect the connectors and wiring. Look for rubbing, scraping, bare wires, worn spots or melted plastic connectors.

Process Tips

Diagnostic trouble code U1679 is not difficult to diagnose and repair. Thus, it always pays to have a qualified technician to look after your vehicle should this error code arise.

Diagnosing this code requires the engine to be in good running shape, without unmetered air entering the engine. If other codes that relates to misfiring condition, lean running or air entering the engine is present, then you must first fix those error codes before U1679.

Fortunately, U1679 is a fairly common OBD code, meaning that it applies to all makes and models of vehicles made after 1996.

U1679 Trouble Code For Specific Cars

U1679 Britannia Gt Crankshaft Position Sensor B Circuit Low Input
U1679 Fiat Panda Lamp Turn Signal Rear Output Circuit Short To Ground
U1679 Lancia Voyager Starter Motor Circuit Failure
U1679 Princess 2200 Fuel Rail/System Pressure - Too High
U1679 Packard Eight Driver Door Ajar Circuit Open
U1679 Mercury Messenger Air Suspension Rear Height Sensor High (SE) Signal Circuit Open
U1679 Oldsmobile Eight Cylinder 9 Contribution/Balance Fault