DF138 BMW Fault Code

Description:

The Camshaft Position sensor will signal the Engine Control Module when the #1 cylinder is ready for the spark plug to fire (top-dead-center on compression stroke).

The ECM uses the information from this sensor to help calculate fuel delivery and spark timing.

DF138 Code Symptoms :

The original multi-displacement system turned off opposite pairs of cylinders, allowing the engine to have three different configurations and displacements. DF138 code had an elaborate diagnostics procedure, including showing engine trouble codes on the air conditionning display. However, the system was troublesome, misunderstood by customers, and a rash of unpredictable failures led to the technology being quickly retired.

Diagnosis And Repairing DF138

DF138 OBD 2 code on vehicles with electronically controlled automatic transmissions, the 3-4 shift solenoid is responsible for actuating the hydraulic circuits to activate clutches or bands that change gears inside the automatic transmission.

How to fix DF138 code ?

• Exhaust gas leaks
• Faulty Fuel injector
• Foreign matter caught in fuel filler cap
• Faulty ignition coil (s)

Some systems require that the actuator has an adequate supply of brake fluid. Low brake fluid levels can mimic the symptoms of code DF138, so consult the manual to locate the brake fluid reservoir.

Bear in mind that a low fluid level can set code DF138 on some applications, so make sure that on fluid operated systems the fluid level is up to the mark before starting an electrical diagnosis.