Lexus NX: Drive Motor "B" Current Sensor Circuit (P0A55-687)
DESCRIPTION
The MG ECU, which is built into the inverter with converter assembly, monitors its internal operation and will store DTCs if it detects a malfunction.
HINT:
The term "drive motor B" indicates the rear motor (MGR).
| DTC No. | Detection Item | DTC Detection Condition | Trouble Area | MIL | Warning Indicate |
|---|---|---|---|---|---|
| P0A55-687 | Drive Motor "B" Current Sensor Circuit | Motor current sensor high resolution circuit signal is out of range or there is a difference between it and the motor current sensor low resolution circuit current value. (1 trip detection logic) |
| Does not come on | Master Warning Light: Comes on |
CAUTION / NOTICE / HINT
CAUTION:
- Before inspecting the high-voltage system or disconnecting the low voltage connector of the inverter with converter assembly, take safety precautions such as wearing insulated gloves and removing the service plug grip to prevent electrical shocks. After removing the service plug grip, put it in your pocket to prevent other technicians from accidentally reconnecting it while you are working on the high-voltage system.
-
After removing the service plug grip, wait for at least 10 minutes before touching any of the high-voltage connectors or terminals. After waiting for 10 minutes, check the voltage at the terminals in the inspection point in the inverter with converter assembly. The voltage should be 0 V before beginning work.
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HINT:
Waiting for at least 10 minutes is required to discharge the high-voltage capacitor inside the inverter with converter assembly.
NOTICE:
After turning the power switch off, waiting time may be required before disconnecting the cable from the negative (-) auxiliary battery terminal. Therefore, make sure to read the disconnecting the cable from the negative (-) auxiliary battery terminal notices before proceeding with work.
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HINT:
After the repair, clear the DTCs and perform the following procedure to check that DTCs are not output.
- Turn the power switch on (IG) and wait for 5 seconds or more.
PROCEDURE
| 1. | CHECK DTC OUTPUT (HYBRID CONTROL) |
(a) Connect the Techstream to the DLC3.
(b) Turn the power switch on (IG).
(c) Enter the following menus: Powertrain / Hybrid Control / Trouble Codes.
(d) Check for DTCs.
Powertrain > Hybrid Control > Trouble Codes| Result | Proceed to |
|---|---|
| P0A55-687 only is output, or DTCs except the ones in the table below are also output. | A |
| Any of the following DTCs are also output. | B |
| Relevant DTC | |
|---|---|
| P0A1C-693 | Drive Motor "B" Control Module |
| P0A46-695 | Drive Motor "B" Position Sensor Circuit Range / Performance |
| P0A51-174 | Drive Motor "A" Current Sensor Circuit |
| P0A79-694, 712 | Drive Motor "B" Inverter Performance |
| P0BF6-683 | Drive Motor "B" Phase V Current Sensor Circuit Range / Performance |
| P0BFA-685 | Drive Motor "B" Phase W Current Sensor Circuit Range / Performance |
| P1C6F-688 | Drive Motor "B" Phase V Current Sensor Offset Range / Performance |
| P1C70-689 | Drive Motor "B" Phase W Current Sensor Offset Range / Performance |
| P33C1-684 | Drive Motor "B" Phase V Current Sensor Sub Circuit Range / Performance |
| P33C6-686 | Drive Motor "B" Phase W Current Sensor Sub Circuit Range / Performance |
| P33D8-677 | Drive Motor "B" Phase V Current Sensor Correlation |
| P33D9-678 | Drive Motor "A" Phase W Current Sensor Correlation |
HINT:
- P0A55-687 may be stored due to a malfunction which causes the DTCs in the preceding table to be stored. In this case, first troubleshoot the output DTCs in the preceding table. Then, perform a reproduction test to check that no DTCs are output.
(e) Turn the power switch off.
| B | .gif) | GO TO DTC CHART (HYBRID CONTROL SYSTEM) |
|
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| 2. | CHECK CONNECTOR CONNECTION CONDITION (INVERTER WITH CONVERTER ASSEMBLY CONNECTOR) |
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| Result | Proceed to |
|---|---|
| OK | A |
| NG (The connector is not connected securely.) | B |
| NG (The terminals are not making secure contact or are deformed, or water or foreign matter exists in the connector.) | C |
| A | | REPLACE INVERTER WITH CONVERTER ASSEMBLY |
| B | | CONNECT SECURELY |
| C | | REPAIR OR REPLACE HARNESS OR CONNECTOR |
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Components
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How To Proceed With Troubleshooting
CAUTION / NOTICE / HINT HINT:
Use the following procedure to troubleshoot the air conditioning system.
*: Use the Techstream.
PROCEDURE 1. VEHICLE BROUGHT TO WORKSHOP
NEXT 2. INSPECT AUXILIARY BATTERY VOLTAGE (a) Inspect the auxiliary battery voltage with t
