Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Diagnostic Trouble Code Chart
- DOOR ECU
Standard [Power window regulator master switch (driver's door ECU)]:
POWER WINDOW DIAGNOSIS STANDARDSAE code (See) Item Diagnosis B1231 (POWER WINDOW REGULATOR MOTOR ASSY LH LIMIT SWITCH AND PULSE SENSOR CIRCUIT (DRIVER'S DOOR) ) Driver's side jam protection limit switch malfunctions Driver side power window regulator motor assembly open in limit switch system B1232 (POWER WINDOW REGULATOR MOTOR ASSY LH LIMIT SWITCH AND PULSE SENSOR CIRCUIT (DRIVER'S DOOR) ) Driver's side jam protection sensor malfunctions Driver side power window regulator motor assembly open or short in pulse sensor system Standard [Power window regulator switch (passenger's door ECU)]:
POWER WINDOW DIAGNOSIS STANDARDSAE code (See) Item Diagnosis B1233 (POWER WINDOW REGULATOR MOTOR ASSY RH LIMIT SWITCH AND PULSE SENSOR CIRCUIT (PASSENGER'S DOOR) ) Passenger's side jam protection limit switch malfunctions Passenger side power window regulator motor assembly RH open in limit switch system B1234 (POWER WINDOW REGULATOR MOTOR ASSY RH LIMIT SWITCH AND PULSE SENSOR CIRCUIT (PASSENGER'S DOOR) ) Passenger's side jam protection sensor malfunctions Passenger side power window regulator motor assembly RH open or short in pulse sensor system - Driver side J/B (body ECU) (Data list of switch signal by DTC check)
Standard [Driver side J/B (body ECU)]:
HINT:
DTC No. B1221 and B1223 are the codes to inform of each switch condition and will be output when the switch is ON. In that these codes are displayed operating the switch or the switch or the codes are not displayed even with operating the switch, there may be trouble in the switch circuit.
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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