P0157 Dixi 6 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. If the car doesn't start, they will proceed by testing the voltage at the fuel pump connector and see if the fuel pump relay, fuse, and PCM circuitry should be inspected.
Possible Causes :
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. It should be pretty close to battery voltage (12 volts). If not, then this is the circuit that has the problem.
Diagnostic trouble code P0157 Dixi 6 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 P0157 Dixi 6.
Fortunately, P0157 Dixi 6 is a fairly common OBD code, meaning that it applies to all makes and models of vehicles made after 1996.