INSPECTION PROCEDURE B-1: Lamp reminder buzzer function does not work normally.


caution Whenever the ECU is replaced, ensure that the input and output signal circuits are normal.


COMMENTS ON TROUBLE SYMPTOM
The ETACS-ECU operates this function in accordance with the input signals below.

  • Ignition switch (IG1)
  • Driver’s door switch
  • Tail lamp switch
  • Headlamp switch
If this function does not work normally, these input signal circuit(s) or the ETACS-ECU may be defective.

POSSIBLE CAUSES

  • Malfunction of the driver’s door switch
  • Malfunction of the column switch
  • Malfunction of the ETACS-ECU
  • Damaged harness wires and connectors

DIAGNOSTIC PROCEDURE

Step 1. Check the power supply circuit.
When the ignition switch is turned to the LOCK (OFF) position, check if the hazard warning lamps illuminate.

Q. Is the check result normal?
Go to Step 2.
Refer to inspection procedure A-2 "Check the ETACS-ECU battery power supply circuit ."

Step 2. Pulse check
Check the input signals below, which are related to the lamp reminder buzzer function.
System switch
 Check condition
Ignition switch (IG1)
 When turned from ACC to ON
Driver’s door switch
 When the driver’s door is opened
Tail lamp switch
 When the lighting switch is turned to the TAIL position
Headlamp switch
 When the lighting switch is turned to the HEADLAMP position
OK: The M.U.T.-III sounds or the voltmeter needle fluctuates.

Q. Are the check result normal?
All the signals are received normally. : Go to Step 3.
The ignition switch (IG1) signal is not received. : Refer to inspection procedure P-2 "The ignition switch (IG1) signal is not received ."
The driver’s door switch signal is not received. : Refer to inspection procedure P-5 "The driver’s door switch signal is not received <LH drive vehicles> or <RH drive vehicles>."
The tail lamp switch signal is not received. : Refer to inspection procedure P-6 "The column switch (lighting and turn-signal lamp switch) signal is not received ."
The headlamp switch signal is not received. : Refer to inspection procedure P-6 "The column switch (lighting and turn-signal lamp switch) signal is not received ."

Step 3. Retest the system.
The lamp reminder buzzer function should work normally.

Q. Is the check result normal?
The trouble can be an intermittent malfunction (Refer to GROUP 00 - How to Cope with Intermittent Malfunction ).
Replace the ETACS-ECU.