B1373 Toyota Previa Diagnostic Trouble Code

B1373 Toyota Previa code definition:
B1373 is a kind of OBD-II Diagnostic B-Body Diagnostic Trouble Code for Toyota Previa.

B1373 Toyota Previa is defined as Camshaft Position Sensor A Circuit Low. This means the CMP (camshaft position) sensor circuit on engine bank 1 sends an irregular reading. Any code that causes the vehicle's engine to die while running should be fixed as soon as possible, as it can be dangerous for both the vehicle and the passengers of the vehicle.

Symptoms

Symptoms of a B1373 Toyota Previa diagnostic trouble code may include:

The engine oil will exhibit dilution from the ECUs attempts to increase engine temperature. Some vehicles advance the fuel injection timing slightly after top center to afterburn a small amount of fuel to increase exhaust temperatures. Some of this fuel enters the crankcase. When the ECU determines the necessity to regenerate the DPF, the service life of the oil be shortened significantly
Faulty or damaged wiring
Hesitation upon acceleration
Reduction in engine performance, especially at low RPM levels

Possible Causes :

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.
Some aftermarket accessories and performance modifications
Defective ECU strategies or components will prevent proper regeneration

Common Misdiagnoses

Exhaust Gas Recirculation System Valve 1 Problem
BBV Sensor Circuit Low Voltage Problem
Transmission Engaged At High Throttle Angle Problem
Cruise Inhibit Control Circuit Problem
TFP Valve Position Switch-Drive Without Drive Ratio Problem

Repair Processes :

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. You might continue by connecting the scanner to the vehicle diagnostic connector and retrieving all stored codes and freeze frame data. If the engine displays a miss and there wasn't a code, determine which cylinder is misfiring. If the exhaust manifold is visible, spay or pour a small amount of water on each cylinder exhaust port. Water will evaporate immediately on good cylinders and slowly on the missing cylinder. If this can't be accomplished pull the plugs and check the condition.

Process Tips

Diagnostic trouble code B1373 Toyota Previa 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 B1373 Toyota Previa.

Fortunately, B1373 Toyota Previa is a fairly common OBD code, meaning that it applies to all makes and models of vehicles made after 1996.