Inspection Procedure N-1
INSPECTION PROCEDURE N-1: ETACS-ECU does not receive any signal from the key reminder switch.
CIRCUIT OPERATION
The ETACS-ECU operates the following functions or systems according to signal from the key reminder switch:
- Ignition key reminder tone alarm function
- Forgotten key reminder
- Keyless entry system
- Timed locking mechanism
- Dome light dimming function
- Ignition key cylinder illumination light
TECHNICAL DESCRIPTION (COMMENT)
If the signal is not normal, the functions or systems described in "CIRCUIT OPERATION" do not work normally.
TROUBLESHOOTING HINTS
- The key reminder switch may be defective
- The wiring harness or connectors may have loose, corroded, or damaged terminals, or terminals pushed back in the connector
- The ETACS-ECU may be defective
DIAGNOSIS
Required Special Tools:
- MB991223: Harness Set
- MB992006: Extra Fine Probe
STEP 1. Check key reminder switch connector C-310 for loose, corroded or damaged terminals, or terminals pushed back in the connector.
Q. Is key reminder switch connector C-310 in good condition?
YES Go to Step 2.
NO Repair or replace the damaged component(s). Harness Connector Inspection. If the functions described in "CIRCUIT OPERATION" work normally, the input signal from the key reminder switch should be normal.
STEP 2. Check the key reminder switch.
Disconnect key reminder switch connector C-310. Then check continuity between terminals.
Q. Is the key reminder switch in good condition?
YES Go to Step 3.
NO Replace the key reminder switch. If the functions described in "CIRCUIT OPERATION" work normally, the input signal from the key reminder switch should be normal.
STEP 3. Check the ground circuit to the key reminder switch. Measure the resistance at key reminder switch connector C-310.
(1)Disconnect key reminder switch connector C-310 and measure the resistance available at the wiring harness side of the connector.
(2)Measure the resistance value between terminal 4 and ground.
- The resistance should be 2 ohms or less.
Q. Is the measured resistance 2 ohms or less?
YES Go to Step 5.
NO Go to Step 4.
STEP 4. Check the wiring harness between key reminder switch connector C-310 (terminal 4) and ground.
- Check the ground wire for open circuit.
Q. Is the wiring harness between key reminder switch connector C-310 (terminal 4) and ground in good condition?
YES No action is necessary and testing is complete.
NO The wiring harness may be damaged or the connector(s) may have loose, corroded or damaged terminals, or terminals pushed back in the connector. Repair the wiring harness as necessary. If the functions described in "CIRCUIT OPERATION" work normally, the input signal from the key reminder switch should be normal.
STEP 5. Check ETACS-ECU connector C-219 for loose, corroded or damaged terminals, or terminals pushed back in the connector.
Q. Is ETACS-ECU connector C-219 in good condition?
YES Go to Step 6.
NO Repair or replace the damaged component(s). Harness Connector Inspection. If the functions described in "CIRCUIT OPERATION" work normally, the input signal from the key reminder switch should be normal.
STEP 6. Check the wiring harness between key reminder switch connector C-310 (terminal 6) and ETACS-ECU connector C-219 (terminal 30).
- Check the communication lines for open circuit and short circuit.
Q. Is the wiring harness between key reminder switch connector C-310 (terminal 6) and ETACS-ECU connector C-219 (terminal 30) in good condition?
YES Replace the ETACS-ECU. When the ETACS-ECU is replaced, register the encrypted code. Encrypted Code Registration Criteria Table. If the functions described in "CIRCUIT OPERATION" work normally, the input signal from the key reminder switch should be normal.
NO The wiring harness may be damaged or the connector(s) may have loose, corroded or damaged terminals, or terminals pushed back in the connector. Repair the wiring harness as necessary. If the functions described in "CIRCUIT OPERATION" work normally, the input signal from the key reminder switch should be normal.