U3745 Diagnostic Trouble Code

U3745 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 U3745 diagnostic trouble code may include:

The light may stay on or light intermittently as the DPF regenerates. The engine will be sluggish on acceleration.
Faulty PCM
If the DPF is not cleared the ECU will revert to the "Limp Home Mode" until the situation is corrected
Diminished fuel efficiency

Possible Causes :

An air leak forward of the DPF will change the sensor readings resulting in the code
Rusty exhaust systems, cracked exhaust manifolds or damaged or missing gaskets or donuts will cause air leaks.
Fuel with a large percentage of sulfur will clog the DPF quickly

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.

Process Tips

Diagnostic trouble code U3745 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 U3745.

Fortunately, U3745 is a fairly common OBD code, meaning that it applies to all makes and models of vehicles made after 1996.

U3745 Trouble Code For Specific Cars

U3745 Ford Explorer V Memory Off Switch Circuit Short to Battery
U3745 Reliant Regal Gate Select Actuator Circuit Range/Performance
U3745 Mg Zt-t ANTI THEFT HORN OUTPUT CIRCUIT Failure
U3745 Peugeot 407 EIC Switch-1 Assembly Circuit Open
U3745 Mitsubishi Lancer Evo 9 Aux A/C Blower Speed 1 Circuit Failure
U3745 Chevrolet Aveo Driver Door Handle Circuit Short To Ground
U3745 Hsv Grange Ride Control RF Shock Actuator Circuit Short To Ground