C1388 BMW Fault Code

Description:

BMW Mass Air Flow (MAF) Sensor Intermittent The MAF sensor circuit is monitored by the PCM for sudden voltage (or air flow) input change through the comprehensive component monitor (CCM).

If during the last 40 warm-up cycles in key ON engine running the PCM detects a voltage (or air flow) change beyond the minimum or maximum calibrated limit, a continuous memory diagnostic trouble code (DTC) is stored.

C1388 Code Symptoms :

There are currently two main types of cylinder deactivation used today, depending on the type of engine. C1388 code for the pushrod design which uses solenoids to alter the oil pressure delivered to the lifters. In their collapsed state, the lifters are unable to elevate their companion pushrods under the valve rocker arms, resulting in valves that cannot be actuated and remain closed.

Diagnosis And Repairing C1388

C1388 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 C1388 code ?

• Failures of clutch motion/travel sensors.
• Engine Control Module (ECM)
• Faulty Camshaft Position Sensor
• Fuel filler cap remains open or fails to close

Some systems require that the actuator has an adequate supply of brake fluid. Low brake fluid levels can mimic the symptoms of code C1388, so consult the manual to locate the brake fluid reservoir.

Bear in mind that a low fluid level can set code C1388 on some applications, so make sure that on fluid operated systems the fluid level is up to the mark before starting an electrical diagnosis.