B1021 BMW Fault Code

Description:

Engine Coolant Temperature (ECT) Circuit High Input Indicates the sensor signal is greater than Self-Test maximum. The ECT sensor maximum is 4.6 volts or -50 C (-58 F). Note on some vehicles that are not equipped with an ECT sensor, CHT can be used and can set this DTC. Open circuit in harness Sensor signal short to power Damaged PCM Improper harness connection Damaged sensor ECT V PID reading greater than 4.6 volts with key ON and engine OFF or during any engine operating mode indicates a hard fault.

B1021 Code Symptoms :

If your B1021 check engine light is illuminated, it's best to take it in for diagnostic testing, which can feel like a hassle. Because while the lights vary in appearance from vehicle to vehicle, all have the same basic meaning: There's a problem with the car's emissions system. The on-board diagnostics system B1021 and engine control unit are in charge of monitoring a bunch of different , and if they get a reading that's a little out of whack, up pops the check engine light.

Diagnosis And Repairing B1021

B1021 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 B1021 code ?

• Camshaft advance mechanism binding (VCT unit)
• Clogged or faulty fuel injector (s)
• Fuel injector leaks

Some systems require that the actuator has an adequate supply of brake fluid. Low brake fluid levels can mimic the symptoms of code B1021, so consult the manual to locate the brake fluid reservoir.

Bear in mind that a low fluid level can set code B1021 on some applications, so make sure that on fluid operated systems the fluid level is up to the mark before starting an electrical diagnosis.