U1253 Diagnostic Trouble Code

U1253 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 U1253 diagnostic trouble code may include:

Hesitation upon acceleration
Excessive exhaust leak
Rich or lean exhaust
If the DPF is not cleared the ECU will revert to the "Limp Home Mode" until the situation is corrected

Possible Causes :

A large air leak at or near the number one oxygen sensor would also cause a lean mixture.
Faulty IMRC actuator relay (if equipped)
Some aftermarket accessories and performance modifications

Repair Processes :

Look for rubbing, scraping, bare wires, worn spots or melted plastic connectors. Pull the connectors apart and carefully look at the terminals (the metal parts) inside the connectors. 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 U1253 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 U1253.

Fortunately, U1253 is a fairly common OBD code, meaning that it applies to all makes and models of vehicles made after 1996.

U1253 Trouble Code For Specific Cars

U1253 Nsu 1000 Cylinder 10 Misfire Detected
U1253 Ssangyong Tivoli Lamp Headlamp Input Circuit Open
U1253 Oka City Cylinder 4 Injector Circuit High
U1253 Saab 9.5 Ii Ignition Run/Acc Circuit Short To Ground
U1253 Simca 1307 Intake Manifold Runner Control Circuit Malfunction
U1253 Renault Argos Gear Shift Foward Actuator Circuit High
U1253 Gaz M-21 O2 Sensor Heater Circuit Malfunction (Bank 1 Sensor 1)