Inspection Procedure M-1
ETACS-ECU does not Receive a Signal from the Key Reminder SwitchKey Reminder Switch Input Circuit:
Connectors:
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
- Keyless entry system
- Dome light dimming function
TECHNICAL DESCRIPTION (COMMENT)
If the signal is not normal, the functions or systems, which are described in "CIRCUIT OPERATION", do not work normally.
TROUBLESHOOTING HINTS
- Malfunction of the key reminder switch
- Malfunction of the ETACS-ECU
- Damaged harness wires or connectors
DIAGNOSIS
Required Special Tools:
- MB991223: Test Harness Set
- MB991502: Scan Tool (MUT-II)
STEP 1. Check the key reminder switch.
Disconnect key reminder switch connector C-207. Then check continuity between terminals.
Q: Is the key reminder switch in good condition?
YES: Go to Step 2.
NO: Replace the key reminder switch. If the functions, which are described in "CIRCUIT OPERATION", work normally, the input signal from the key reminder switch should be normal.
STEP 2. Measure at key reminder switch connector C-207 in order to the ground circuit to the key reminder switch.
1. Disconnect key reminder switch connector C-207, and measure at the wiring harness side.
2. Measure the resistance value between terminal 4 and ground.
- The measured value should be 2 Ohm or less.
Q: Does the measured resistance value correspond with this range?
YES: Go to Step 5.
NO: Go to Step 3.
STEP 3. Check key reminder switch connector C-207 for damage.
Q: Is key reminder switch connector C-207 in good condition?
YES: Go to Step 4.
NO: Repair or replace the connector. Refer to Harness Connector Inspection. If the functions, which are described in "CIRCUIT OPERATION", work normally, the input signal from the key reminder switch should be normal
STEP 4. Check the wiring harness between key reminder switch connector C-207 and ground.
NOTE: Also check joint connector C-06. If joint connector C-06 is damaged, repair or replace the connector as described in Harness Connector Inspection.
Q: Is the wiring harness between key reminder switch connector C-207 and ground in good condition?
YES: No action to be taken.
NO: Repair the wiring harness. If the functions, which are described in "CIRCUIT OPERATION", work normally, the input signal from the key reminder switch should be normal.
STEP 5. Check key reminder switch connector C-207 and ETACS-ECU connector C-227 for damage.
Q: Are key reminder switch connector C-207 and ETACS-ECU connector C-227 in good condition?
YES: Go to Step 6.
NO: Repair or replace the connector. Refer to Harness Connector Inspection. If the functions, which are 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-207 and ETACS-ECU connector C-227.
Q: Is the wiring harness between key reminder switch connector C-207 and ETACS-ECU connector C-227 in good condition?
YES: Replace the ETACS-ECU. If the functions, which are described in "CIRCUIT OPERATION", work normally, the input signal from the key reminder switch should be normal.
NO: Repair the wiring harness. If the functions, which are described in "CIRCUIT OPERATION", work normally, the input signal from the key reminder switch should be normal.