B1274
B1274Component Location:
General Description
Power sliding door (hereinafter PSD) is the system which moves sliding door of vehicle by electronic motor so that user can open or close door with less force than required on manual operation. PSD consists of drive unit, center roller/rail, handle and various kinds of switch (anti pinch, detent, latch), Drive unit is located at rear quarter panel that is between C pillar and D pillar. It is core part of PSD that drives cable by force of motor to move sliding door, beside that Drive unit consists of PSD ECU.door motor.clutch,optical sensor.cable and warning buzzer. Drive unit cable moves door by transmitting driving force of door motor through center roller and is located at cable drum which is between pinion interpretor and clutch assembly.
DTC Description
The ECM sets DTC B1274 if cable of drive unit is broken.
DTC Detecting Condition:
Schematic Diagram:
Signal Waveform:
Monitor Scantool Data
1. Connect scantool to Data Link Connector (DLC).
2. Ignition "ON" & engine "OFF" & PSD "ON"
3. Select "Diagnostic Trouble Codes (DTCs)"mode and monitor "DTC Status" parameter.
4. Is the DTC B1274 present?
YES - Go to "Inspection & Repair" procedure.
NO - Fault is intermittent caused by poor contact in the sensor's and/or ECM's connector or was repaired and ECM memory was not cleared. Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage. Repair or replace as necessary and then go to "Verification of Vehicle Repair" procedure.
Terminal and Connector Inspection
1. Many malfunctions in the electrical system are caused by poor harness and terminals.
Faults can also be caused by interference from other electrical systems, and mechanical or chemical damage.
2. Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage.
3. Has a problem been found?
YES - Repair as necessary and go to "Verification Vehicle Repair" procedure.
NO - Go to "W/Harness Inspection" procedure.
Component Inspection
1. Check optical sensor
1. Ignition "ON" & engine "OFF"
2. Measure waveform between terminal "F26-2.4 F25-2.4" of optical sensor and chassis ground. While operating PSD
Specification : no waveform
3. Is waveform measured near the specification?
YES - Go to "Check drive unit" procedure.
NO - Substitute with a known-good drive unit and check for proper operation. If the problem is corrected, replace drive unit and then go to "Verification Vehicle Repair" procedure.
CAUTION: It is impossible to change Optical sensor separately. So it is changed by drive unit when change is necessary
2. Check drive unit
4. Ignition "ON" & engine "OFF" & PSD "ON"
5. Close the PSD until door is at latch position.
6. Measure waveform between terminal "F28-2-18,23, F27-2-18,23" of optical sensor and chassis ground. While pushing PSD close switch.
Specification : no waveform
7. Is waveform measured near the specification?
YES - Check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage. Repair or replace as necessary and then go to "Verification of Vehicle Repair" procedure.
NO - Substitute with a known-good drive unit and check for proper operation. If the problem is corrected, replace drive unit and then go to "Verification Vehicle Repair" procedure.
Verification of Vehicle Repair
After a repair, it is essential to verify that the fault has been corrected.
1. Connect scantool and select "Diagnostic Trouble Codes (DTCs)" mode and then clear DTC.
2. Operate the vehicle and monitor the DTC on the scantool.
3. Are any DTCs present?
YES - Go to the applicable troubleshooting procedure.
NO - System is performing to specification at this time.