Inspection Procedure 2
Inspection Procedure 2: Defective Power Supply System Of The Ignition SwitchIgnition Switch Power Supply Circuit:
TECHNICAL DESCRIPTION (COMMENT)
When the power supply system of ignition switch has a problem, none of the equipment and system connected to the ignition switch works even if the ignition switch is operated.
TROUBLESHOOTING HINTS
- The ignition switch may be defective
- The fuse No.14 may be defective
- The ETACS-ECU may be defective
- The wiring harness or connectors may have loose, corroded, or damaged terminals, or terminals pushed back in the connector
DIAGNOSIS
Required Special Tools:
- MB992006: Extra fine probe
- MB991223: Harness set
STEP 1. Check ignition switch connector C-210 for loose, corroded or damaged terminals, or terminals pushed back in the connector.
Q:Is ignition switch connector C-210 in good condition?
YES : Go to Step 2.
NO : Repair the defective connector.
STEP 2. Check the battery power supply circuit to the ignition switch. Measure the voltage at ignition switch connector C-210.
1. Disconnect the connector, and measure at the wiring harness side.
2. Measure the voltage between terminal 1 and ground.
- The voltage should measure approximately 12 volts (battery positive voltage).
Q: Is the measured voltage approximately 12 volts (battery positive voltage)?
YES : Go to Step 6.
NO : Go to Step 3.
STEP 3. Check the fuse No.14.
Q: Is the check result normal?
YES : Go to Step 4.
NO : Replace the fuse No.14. (Check that there is not a short to ground in the circuit of lower reaches before replacing. If there are any problems, replace the fuse after the circuit of lower reaches is repaired.)
STEP 4. Check ETACS-ECU connector C-317 for loose, corroded or damaged terminals, or terminals pushed back in the connector.
Q:Is ETACS-ECU connector C-317 in good condition?
YES : Go to Step 5.
NO : Repair the damaged parts.
STEP 5. Check the Wiring harness between ignition switch connector C-210 (terminal No.1) and ETACS-ECU connector C-317 (terminal No.3).
- Check the battery power supply line for open circuit.
Q:Is the check result normal?
YES : Go to Step 7.
NO : Repair the wiring harness.
STEP 6. Check the ignition switch.
Remove the ignition switch. Then check continuity between the switch terminal.
Q:Is the ignition switch in good condition?
YES : Go to Step 7.
NO : Replace the ignition switch.
STEP 7. Retest the system.
Q :When the ignition switch is operated, do the equipment and system work normally?
YES : The trouble can be an intermittent malfunction.
NO : Replace the ETACS-ECU.