B1128

Factory Manual References

Factory service manual diagnostic procedure for 2009 acura csx

DTC B1128: Driver's Door Lock Switch Signal Error (LOCK/UNLOCK)

NOTE: If you are troubleshooting multiple DTCs, be sure to follow the instructions in B-CAN System Diagnosis Test Mode A (see TROUBLESHOOTING - B-CAN SYSTEM DIAGNOSIS TEST MODE A ).
  1. Clear the DTCs with the HDS.
  2. Turn the ignition switch OFF, and then back ON (II).
  3. Operate the driver's door lock switch LOCK/UNLOCK several times.
  4. Check for DTCs with the HDS.

    Is DTC B1128 indicated? 

    YES  -Go to step 5.

    NO  -Intermittent failure. The driver's door lock system is OK at this time.

  5. With the driver's door lock switch in the neutral position, select KEYLESS from the HDS and enter the DATA LIST.
  6. Check the ON/OFF information of the DRIVER'S DOOR LOCK SWITCH (LOCK) and DRIVER'S DOOR LOCK SWITCH (UNLOCK) in the DATA LIST.

    Are both information indicators OFF? 

    YES  -Go to step  12.

    NO  -Go to step 7.

  7. Disconnect the driver's power window switch 22P connector.
  8. Check the ON/OFF information of the DRIVER'S DOOR LOCK SWITCH (LOCK) and DRIVER'S DOOR LOCK SWITCH (UNLOCK) in the DATA LIST.

    Are both information indicators OFF? 

    YES  -Faulty door lock switch; replace the driver's power window switch.

    NO  -Go to step 9.

  9. Turn the ignition switch OFF.
  10. Disconnect the under-dash fuse/relay box connector T (34P).
  11. Check for continuity between the No. 28 (LOCK) and No. 27 (UNLOCK) terminals of the under-dash fuse/relay box connector T (34P) and body ground.
    Fig 1: Checking Continuity Between 28 (LOCK) And 27 (UNLOCK) Terminals Of Under-Dash Fuse/Relay Box Connector T (34P) And Body Ground
    G06269270Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Are there continuity? 

    YES  -Repair a short in the LOCK or UNLOCK wire.

    NO  -Faulty MICU, replace the under-dash fuse/relay box.

  12. Turn the ignition switch OFF.
  13. Disconnect the power window master switch 22P connector.
  14. Disconnect under-dash fuse/relay box connector T (34P).
  15. Check for continuity between the No. 28 (LOCK) and No. 27 (UNLOCK) terminals of the under-dash fuse/relay box connector T (34P).
    Fig 2: Checking Continuity Between 28 (LOCK) And 27 (UNLOCK) Terminals Of Under-Dash Fuse/Relay Box Connector T (34P)
    G06269271Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Repair a short in the wire between the LOCK and UNLOCK wires.

    NO  -Substitute a known-good power window master switch, and recheck. If the symptom/indication goes away, replace the original power window master switch. If not, the MICU is faulty, replace the under-dash fuse/relay box.

DTC B1128: Driver's Door Lock Switch Signal Error (LOCK/UNLOCK)

NOTE: If you are troubleshooting multiple DTCs, be sure to follow the instructions in B-CAN System Diagnosis Test Mode A (see TROUBLESHOOTING - B-CAN SYSTEM DIAGNOSIS TEST MODE A ).
  1. Clear the DTCs with the HDS.
  2. Turn the ignition switch OFF, and then back ON (II).
  3. Operate the driver's door lock switch LOCK/UNLOCK several times.
  4. Check for DTCs with the HDS.

    Is DTC B1128 indicated? 

    YES  -Go to step 5.

    NO  -Intermittent failure. The driver's door lock system is OK at this time.

  5. With the driver's door lock switch in the neutral position, select KEYLESS from the HDS and enter the DATA LIST.
  6. Check the ON/OFF information of the DRIVER'S DOOR LOCK SWITCH (LOCK) and DRIVER'S DOOR LOCK SWITCH (UNLOCK) in the DATA LIST.

    Are both information indicators OFF? 

    YES  -Go to step  12.

    NO  -Go to step 7.

  7. Disconnect the driver's power window switch 22P connector.
  8. Check the ON/OFF information of the DRIVER'S DOOR LOCK SWITCH (LOCK) and DRIVER'S DOOR LOCK SWITCH (UNLOCK) in the DATA LIST.

    Are both information indicators OFF? 

    YES  -Faulty door lock switch; replace the driver's power window switch.

    NO  -Go to step 9.

  9. Turn the ignition switch OFF.
  10. Disconnect the under-dash fuse/relay box connector T (34P).
  11. Check for continuity between the No. 28 (LOCK) and No. 27 (UNLOCK) terminals of the under-dash fuse/relay box connector T (34P) and body ground.
    Fig 1: Checking Continuity Between 28 (LOCK) And 27 (UNLOCK) Terminals Of Under-Dash Fuse/Relay Box Connector T (34P) And Body Ground
    G06269270Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Are there continuity? 

    YES  -Repair a short in the LOCK or UNLOCK wire.

    NO  -Faulty MICU, replace the under-dash fuse/relay box.

  12. Turn the ignition switch OFF.
  13. Disconnect the power window master switch 22P connector.
  14. Disconnect under-dash fuse/relay box connector T (34P).
  15. Check for continuity between the No. 28 (LOCK) and No. 27 (UNLOCK) terminals of the under-dash fuse/relay box connector T (34P).
    Fig 2: Checking Continuity Between 28 (LOCK) And 27 (UNLOCK) Terminals Of Under-Dash Fuse/Relay Box Connector T (34P)
    G06269271Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Repair a short in the wire between the LOCK and UNLOCK wires.

    NO  -Substitute a known-good power window master switch, and recheck. If the symptom/indication goes away, replace the original power window master switch. If not, the MICU is faulty, replace the under-dash fuse/relay box.

DTC B1128: Driver's Door Lock Switch Signal Error (LOCK/UNLOCK)

NOTE: If you are troubleshooting multiple DTCs, be sure to follow the instructions in B-CAN System Diagnosis Test Mode A (see TROUBLESHOOTING - B-CAN SYSTEM DIAGNOSIS TEST MODE A ).
  1. Clear the DTCs with the HDS.
  2. Turn the ignition switch OFF, and then back ON (II).
  3. Operate the driver's door lock switch LOCK/UNLOCK several times.
  4. Check for DTCs with the HDS.

    Is DTC B1128 indicated? 

    YES  -Go to step 5.

    NO  -Intermittent failure. The driver's door lock system is OK at this time.

  5. With the driver's door lock switch in the neutral position, select KEYLESS from the HDS and enter the DATA LIST.
  6. Check the ON/OFF information of the DRIVER'S DOOR LOCK SWITCH (LOCK) and DRIVER'S DOOR LOCK SWITCH (UNLOCK) in the DATA LIST.

    Are both information indicators OFF? 

    YES  -Go to step  12.

    NO  -Go to step 7.

  7. Disconnect the driver's power window switch 22P connector.
  8. Check the ON/OFF information of the DRIVER'S DOOR LOCK SWITCH (LOCK) and DRIVER'S DOOR LOCK SWITCH (UNLOCK) in the DATA LIST.

    Are both information indicators OFF? 

    YES  -Faulty door lock switch; replace the driver's power window switch.

    NO  -Go to step 9.

  9. Turn the ignition switch OFF.
  10. Disconnect the under-dash fuse/relay box connector T (34P).
  11. Check for continuity between the No. 28 (LOCK) and No. 27 (UNLOCK) terminals of the under-dash fuse/relay box connector T (34P) and body ground.
    Fig 1: Checking Continuity Between 28 (LOCK) And 27 (UNLOCK) Terminals Of Under-Dash Fuse/Relay Box Connector T (34P) And Body Ground
    G06269270Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Are there continuity? 

    YES  -Repair a short in the LOCK or UNLOCK wire.

    NO  -Faulty MICU, replace the under-dash fuse/relay box.

  12. Turn the ignition switch OFF.
  13. Disconnect the power window master switch 22P connector.
  14. Disconnect under-dash fuse/relay box connector T (34P).
  15. Check for continuity between the No. 28 (LOCK) and No. 27 (UNLOCK) terminals of the under-dash fuse/relay box connector T (34P).
    Fig 2: Checking Continuity Between 28 (LOCK) And 27 (UNLOCK) Terminals Of Under-Dash Fuse/Relay Box Connector T (34P)
    G06269271Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Repair a short in the wire between the LOCK and UNLOCK wires.

    NO  -Substitute a known-good power window master switch, and recheck. If the symptom/indication goes away, replace the original power window master switch. If not, the MICU is faulty, replace the under-dash fuse/relay box.

Supporting Diagrams & Locations

Reference material from the factory manual for this diagnostic procedure.

Diagram

Circuit Diagram

Diagram

Circuit Diagram

Diagram

Circuit Diagram

Diagram

Body Controller Area Network (B-CAN) and Fast Controller Area Network (F-CAN)

Diagram

Circuit Diagram

Diagram

Circuit Diagram

Location

Component Location Index

Location

Component Location Index

Location

Component Location Index

Location

Component Location Index

Fuse/Relay

DTC B1026: Front Passenger's Door Lock Switch Signal Error

Fuse/Relay

DTC B1127: Driver's Door Key Cylinder Switch Signal Error

Fuse/Relay

DTC B1128: Driver's Door Lock Switch Signal Error (LOCK/UNLOCK)

Fuse/Relay

DTC B1129: Driver's Door Lock Knob Switch Signal Error (LOCK/UNLOCK)

Related Procedures

Procedure

Delete or add multiple keys

Procedure

Doors automatically relock after being unlocked with the transmitter even though a door has been opened

Procedure

AM/FM Antenna Amplifier Replacement

Procedure

Auxiliary Jack Assembly Replacement

Procedure

Audio disc cannot be inserted and/or ejected (with navigation)

Procedure

Audio disc does not eject

← Back to 2009 acura csxBrowse vehicle codesDIY Repair Guides