U0690 Diagnostic Trouble Code

U0690 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 U0690 diagnostic trouble code may include:

Poor acceleration
Cherry red hot catalytic converter
Possible spark knock (detonation / pre-ignition)
Rich or lean exhaust

Possible Causes :

Faulty IMRC actuator relay (if equipped)
A large air leak at or near the number one oxygen sensor would also cause a lean mixture.
A plugged converter will cause of host of driveability problems as well as set this code. A severely plugged converter will result in the inability to increase rpm when under load. Look for a code such as P0421 -- catalytic converter efficiency below threshold if the converter indicating a faulty converter.

Repair Processes :

If all testing has passed so far yet you still have the same code, check your scan tool and see if it can open and close the IMRC valve. Look for missing ground strap or a rusty ground where the fuel tank is grounded to the frame. Check for damage to the wiring harness connector. Oxygen sensors signal the engine management computer the amount of oxygen present in the exhaust, which is used in determining and controlling the fuel ratio.

Process Tips

Diagnostic trouble code U0690 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 U0690.

Fortunately, U0690 is a fairly common OBD code, meaning that it applies to all makes and models of vehicles made after 1996.

U0690 Trouble Code For Specific Cars

U0690 Renault Ludo Head Lamp Relay Coil Short to Battery
U0690 Ford Prefect Mirror Passenger Horizontal Feedback Potentiometer Circuit Open
U0690 Kia Mohave Seatbelt Driver Pretensioner Circuit Resistance Low on Squib
U0690 Lincoln Navigator Throttle/Pedal Position Sensor/Switch A Circuit Low Input
U0690 Toyota Bandeirante O2 Sensor Circuit High Voltage (Bank 2 Sensor 2)
U0690 Riley Rm Hydraulic Fluid Pressure/ Flow Circuit Short to Gnd
U0690 Lada 2111 Shift Solenoid A Performance