DTC B2321 Driver Side Door ECU Communication Stop |
| DTC No. | DTC Detection Condition | Trouble Area |
| B2321 | Communication between front door window regulator sub-assembly RH*1 or the front door window regulator sub-assembly LH*2 and main body ECU interrupted for 10 seconds or more, or communication wire malfunction. |
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| 1.CLEAR DTC |
Clear DTCs (Click here).
| NEXT | |
| 2.CHECK FOR DTC |
Check for DTCs (Click here).
| Result | Proceed to |
| DTC B2321 is output | A |
| DTC B2321 and B1206 are output | B |
| DTC B2321, B1206 and/or B2325 are output |
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| A | |
| 3.SYSTEM CHECK |
Check the vehicle specifications.
| Result | Proceed to |
| for RHD | A |
| for LHD | B |
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| A | |
| 4.CHECK HARNESS AND CONNECTOR (MASTER SWITCH - REGULATOR RH) |
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Disconnect the E1 power window regulator master switch assembly connector.
Disconnect the E4 front door window regulator sub-assembly RH connector.
Measure the resistance according to the value(s) in the table below.
| Tester Connection | Condition | Specified Condition |
| E1-16 (LIN2) - E4-9 (LIN) | Always | Below 1 Ω |
| E4-9 (LIN) - Body ground | Always | 10 KΩ or higher |
Measure the voltage according to the value(s) in the table below.
| Tester Connection | Condition | Specified Condition |
| E4-9 (LIN) - Body ground | Always | Below 0.5 V |
| *1 | Front view of wire harness connector (to Power Window Regulator Master Switch Assembly) |
| *2 | Front view of wire harness connector (to Front Door Window Regulator Sub-Assembly RH) |
Reconnect the power window regulator master switch assembly connector.
Reconnect the front door window regulator sub-assembly RH connector.
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| OK | |
| 5.CHECK HARNESS AND CONNECTOR (REGULATOR RH - BATTERY AND BODY GROUND) |
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Disconnect the E4 front door window regulator sub-assembly RH connector.
Measure the voltage according to the value(s) in the table below.
| Tester Connection | Condition | Specified Condition |
| E4-2 (B) - Body ground | Always | 11 to 14 V |
Measure the resistance according to the value(s) in the table below.
| Tester Connection | Condition | Specified Condition |
| E4-1 (GND) - Body ground | Always | Below 1 Ω |
| *1 | Front view of wire harness connector (to Front Door Window Regulator Sub-Assembly RH) |
Reconnect the front door window regulator sub-assembly RH connector.
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| OK | |
| 6.REPLACE FRONT DOOR WINDOW REGULATOR SUB-ASSEMBLY RH NORMAL ONE |
Replace the front door window regulator sub-assembly RH with a normally functioning part (Click here).
Clear DTCs (Click here).
| NEXT | |
| 7.RECONFIRM DTC OUTPUT |
Recheck for DTCs (Click here).
| Result | Proceed to |
| DTC B2321 is not output | A |
| DTC B2321 is output | B |
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| A | ||
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| 8.CHECK HARNESS AND CONNECTOR (MASTER SWITCH - REGULATOR LH) |
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Disconnect the F1 power window regulator master switch assembly connector.
Disconnect the F4 front door window regulator sub-assembly LH connector.
Measure the resistance according to the value(s) in the table below.
| Tester Connection | Condition | Specified Condition |
| F1-16 (LIN2) - F4-9 (LIN) | Always | Below 1 Ω |
| F4-9 (LIN) - Body ground | Always | 10 KΩ or higher |
Measure the voltage according to the value(s) in the table below.
| Tester Connection | Condition | Specified Condition |
| F4-9 (LIN) - Body ground | Always | Below 0.5 V |
| *1 | Front view of wire harness connector (to Power Window Regulator Master Switch Assembly) |
| *2 | Front view of wire harness connector (to Front Door Window Regulator Sub-Assembly LH) |
Reconnect the power window regulator master switch assembly connector.
Reconnect the front door window regulator sub-assembly LH connector.
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| OK | |
| 9.CHECK HARNESS AND CONNECTOR (REGULATOR LH - BATTERY AND BODY GROUND) |
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Disconnect the F4 front door window regulator sub-assembly LH connector.
Measure the voltage according to the value(s) in the table below.
| Tester Connection | Condition | Specified Condition |
| F4-2 (B) - Body ground | Always | 11 to 14 V |
Measure the resistance according to the value(s) in the table below.
| Tester Connection | Condition | Specified Condition |
| F4-1 (GND) - Body ground | Always | Below 1 Ω |
| *1 | Front view of wire harness connector (to Front Door Window Regulator Sub-Assembly LH) |
Reconnect the front door window regulator sub-assembly LH connector.
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| OK | |
| 10.REPLACE FRONT DOOR WINDOW REGULATOR SUB-ASSEMBLY LH NORMAL ONE |
Replace the front door window regulator sub-assembly LH with a normally functioning part (Click here).
Clear DTCs (Click here).
| NEXT | |
| 11.RECONFIRM DTC OUTPUT |
Recheck for DTCs (Click here).
| Result | Proceed to |
| DTC B2321 is not output | A |
| DTC B2321 is output | B |
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| A | ||
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