The input turbine speed sensor detects rotation of the input shaft of the input shaft speed sensor transmission. The computer uses that information, along with the output shaft speed sensor to determine if the transmission is operating according to plan. If the computer detects a difference between the input shaft speed , and the expected output shaft speed, it will adjust transmission pump pressure to prevent clutch disc slip. If adding pressure doesn't solve the problem, it will set a trouble code.
Some systems require that the actuator has an adequate supply of brake fluid. Low brake fluid levels can mimic the symptoms of code B1221, so consult the manual to locate the brake fluid reservoir. Bear in mind that a low fluid level can set code B1221 on some applications, so make sure that on fluid operated systems the fluid level is up to the mark before starting an electrical diagnosis.
If your ignition start circuit open 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 B1221 and engine control unit are in charge of monitoring a bunch of different ignition start circuit open, and if they get a reading that's a little out of whack, up pops the check engine light.
Difficulty Level (Soso)
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Repair Time (50 Min.)
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Cost Prediction : $ 40-75 |
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B1221 is a kind of Body Trouble Code
Auto body problems aren't always easy to spot. Diagnosing auto body problems sometimes requires a little know-how. In this section you'll find articles dedicated to teaching you how to diagnose auto body problems. |
You can view according B1221 DTC for your car model. We selected several models to see obd2 solutions click and view it.