B1257 Trouble Code

View B1257 obd/2 error code description and symptoms. B1257 engine photo

Throttle Position (TP) Sensor Intermittent The TP sensor circuit is monitored by the PCM for sudden TP rotation angle (or voltage) input change through the comprehensive component monitor (CCM). If during the last 80 warm-up cycles in key ON engine running the PCM detects a TP rotation angle (or voltage) changes beyond the minimum or maximum calibrated limit, a continuous diagnostic trouble code (DTC) is stored. Poor continuity through the TP sensor connectors Poor continuity through the TP harness Intermittent open or short inside the TP sensor While accessing the TP V PID on the scan tool, lightly tap on the TP sensor or wiggle the TP sensor connector and harness.

Circuit High Input codes like B1257 are mostly caused by defective alternators that develop excessive voltages, although there may be other causes as well, such as short circuits that 'leak' current into a particular system from other, unrelated systems that work on higher voltages. Note that in the case of short circuits that leak power into a control circuit, there is likely to be other, seemingly unrelated trouble codes present along with the code(s) being investigated. Diagnosing a 'high input' code will always involve a thorough testing of the charging system as a first step, followed by measures to isolate the system from all other possible sources of power during resistance, continuity, and reference voltage tests.

B1257 Error Code Repair Process :

If your b1257 air temperature external sensor circuit short to ground 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 B1257 and engine control unit are in charge of monitoring a bunch of different b1257 air temperature external sensor circuit short to ground, and if they get a reading that's a little out of whack, up pops the check engine light.

Common Causes of B1257

A common cause of code B1257 is the failure of B1257 Air Temperature External Sensor Circuit Short To Ground, but there are several other possible causes as well, such as ;

Damaged VCT phaser
Faulty Intake Valve Timing Control Solenoid Valve
Engine Control Module (ECM)
Radio frequency interference (RFI)

B1257 Trouble Code

B1257 Error Code Repair Process :

Common Causes of B1257

B1257 code for all cars