Inspection Procedure 6

Key Reminder Switch Input Circuit:

Connectors:

CIRCUIT OPERATION
The ETACS-ECU receives the input signal from the key reminder switch, and then judges the operation of each function.

TECHNICAL DESCRIPTION (COMMENT)
The key reminder switch input signal is used for judging the operation of the following functions.

Thus, if there is a malfunction, these functions may not operate correctly
- Ignition key tone alarm function
- Forgotten key prevention function
- keyless entry system
- Dome light dimming function
- Theft-alarm function

TROUBLESHOOTING HINTS
- Malfunction of the theft-alarm starter relay
- Malfunction of the key reminder switch
- Malfunction of STARTING SYSTEM
- Malfunction of the ETACS-ECU
- Damaged harness wires and connectors

DIAGNOSIS
Required Special Tools:
MB991223: Test Harness Set
MB991502: Scan Tool (MUT-II)
MB991529: Diagnostic Trouble Code Check Harness




STEP 1. Check the key reminder switch.
1. Remove the driver's side under cover.
2. Remove the column cover lower and upper.
3. Disconnect the wiring connector from the key reminder switch.




4. Check the continuity between the terminal when the ignition key is pulled out of and inserted into the steering lock cylinder.
If the key reminder switch is damaged, repair it. Confirm that the key reminder switch's input signal can be input and inspected, and confirm that the functions listed in the Technical Description (Comment) operate correctly.

If the key reminder switch is in good condition, go to Step 2.

STEP 2. Check the theft-alarm starter relay.







If the theft-alarm starter relay is damaged, replace it. Confirm that the key reminder switch's input signal can be input and inspected, and confirm that the functions listed in the Technical Description (Comment) operate correctly.

If the theft-alarm starter relay is not damaged, go to Step 3.










STEP 3. Check the key reminder switch connector D-16, theft-alarm starter relay connector C-109 and ETACS-ECU connector D-26 for damage.
If the key reminder switch connector D-16, theft-alarm starter relay connector C-109 and ETACS-ECU connector D-26 are damaged, repair or replace them. Refer to Harness Connector Inspection. Confirm that the key reminder switch's input signal can be input and inspected, and confirm that the functions listed in the Technical Description (Comment) operate correctly.

If the connector are in good condition, go to Step 4.







STEP 4. Check the harness wire between key reminder switch connector D-16 and ETACS-ECU connector D-26.









NOTE: After checking intermittent connector C-72 and theft-alarm starter relay connector C-109, check the wires. If intermittent connector C-72 and theft-alarm starter relay connector C-109 are damaged, repair or replace them. Refer to Harness Connector Inspection.

If the harness wire between key reminder switch connector D-16 and ETACS-ECU connector D-26 is damaged, repair it.

Confirm that the key reminder switch's input signal can be input and inspected, and confirm that the functions listed in the Technical Description (Comment) operate correctly.

If the harness wire is in good condition, go to Step 5.




STEP 5. Check the harness wire between key reminder switch connector D-16 and ground.
If the harness wire between key reminder switch connector D-16 and ground is damaged, repair it.

Confirm that the key reminder switch's input signal can be input and inspected, and confirm that the functions listed in the Technical Description (Comment) operate correctly.

If the harness wire is good condition, replace the ETACS-ECU. Confirm that the key reminder switch's input signal can be input and inspected, and confirm that the functions listed in the Technical Description (Comment) operate correctly.