[54B] SMART WIRING SYSTEM (SWS) NOT USING SWS MONITOR <Hong Kong spec.> - - SYMPTOM PROCEDURES - TONE ALARM - INSPECTION PROCEDURE B-5: Downshift inhibitor buzzer does not work normally. <2000-5A/T>PRINT PAGE / INDEX / PRIOR / NEXT
INSPECTION PROCEDURE B-5: Downshift inhibitor buzzer does not work normally. <2000-5A/T>
 CAUTION
 Whenever the ECU is replaced, ensure that the input and output signal circuits are normal.
COMMENTS ON TROUBLE SYMPTOM
The downshift inhibitor buzzer (incorporated in the ETACS-ECU) will sound if the ETACS-ECU receives buzzer signal from the engine-A/T-ECU while the ignition switch (IG1) signal is on. If this function does not work normally, the input signal circuit from the engine-A/T-ECU, the engine-A/T-ECU itself or the ETACS-ECU may be defective.
POSSIBLE CAUSES
  • Malfunction of the door switches
  • Malfunction of the engine-A/T-ECU
  • Malfunction of the ETACS-ECU
  • Damaged harness wires and connectors
DIAGNOSIS PROCEDURE
Step 1. Use the MUT-II/III to confirm a diagnosis code.
Check whether MPI and automatic transmission-related DTCs are set or not.
Q: Is the check result normal?
YES:  Go to Step 2.
NO:  Refer to GROUP 13A - Troubleshooting <2000> or GROUP 13C - Troubleshooting <2400>. Or refer to GROUP 23A - Troubleshooting .
Step 2. MUT-II/III actuator test
Execute actuator test item number 15 (downshift inhibitor buzzer) (Refer to GROUP 23A - Troubleshooting ).
OK: When actuator test item No.15 is executed, the downshift inhibitor buzzer sounds.
Q: Is the check result normal?
YES:  The trouble can be an intermittent malfunction (Refer to GROUP 00 - How to Cope with Intermittent Malfunction ).
NO:  Go to Step 3.
Step 3. Pulse check
Check the input signal from the ignition switch (IG1).
System switch
 Check conditions
Ignition switch (IG1)
 When turned from ACC to ON

OK: The MUT-II/III sounds or the voltmeter needle fluctuates.
Q: Is the check result normal?
YES:  Go to Step 4.
NO:  Refer to inspection procedure P-2 "The ignition switch (IG1) signal is not received" .
Step 4. Connector check: C-109 engine-A/T-ECU connector
Q: Is the check result normal?
YES:  Go to Step 5.
NO:  Repair the connector.
Step 5. Check at the C-109 engine-A/T-ECU connector.
  1. Disconnect the connector, and check at the wiring harness side.
  1. Ignition switch: ON
  1. Connect C-109 engine-A/T-ECU connector terminal No.128 to body earth.
    2. OK: The ETACS-ECU buzzer sounds.
Q: Is the check result normal?
YES:  Go to Step 9.
NO:  Go to Step 6.
Step 6. Connector check: C-220 ETACS-ECU connector
Q: Is the check result normal?
YES:  Go to Step 7.
NO:  Repair the connector.
Step 7. Check the wiring harness between C-109 engine-A/T-ECU connector terminal No.128 and C-220 ETACS-ECU connector terminal No.43.
NOTE: Prior to the wiring harness inspection, check intermediate connector C-106, and repair if necessary.
  • Check the communication lines for open circuit.
Q: Is the check result normal?
YES:  Go to Step 8.
NO:  Repair the connector.
Step 8. Retest the system.
Q: Does the downshift inhibitor buzzer work normally?
YES:  The trouble can be an intermittent malfunction (Refer to GROUP 00 - How to Cope with Intermittent Malfunction ).
NO:  Replace the ETACS-ECU.
Step 9. Retest the system.
Check that the downshift inhibitor buzzer works normally.
Q: Is the check result normal?
YES:  The trouble can be an intermittent malfunction (Refer to GROUP 00 - How to Cope with Intermittent Malfunction ).
NO:  Replace the engine-A/T-ECU.
[54B] SMART WIRING SYSTEM (SWS) NOT USING SWS MONITOR <Hong Kong spec.> - - SYMPTOM PROCEDURES - TONE ALARM - INSPECTION PROCEDURE B-5: Downshift inhibitor buzzer does not work normally. <2000-5A/T>PRINT PAGE / INDEX / PRIOR / NEXT
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