Inspection Procedure 5: Horns do not sound while the theft-alarm system is triggered: Diagnosis
WARNING: This page is about a different car, the 2014 Mitsubishi Outlander. However, it is still accessible from the selected car via links, so may be relevant.
- STEP 1. Using scan tool (M.U.T.-III), read the diagnostic trouble code.
Check if DTC is stored in the ETACS-ECU.
CAUTION: To prevent damage to scan tool (M.U.T.-III), always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool (M.U.T.-III).- Connect scan tool (M.U.T.-III). Refer to "HOW TO CONNECT SCAN TOOL (M.U.T.-III) ."
- Turn the ignition switch to the "ON" position.
- Check whether the ETACS-ECU related DTC is stored.
- Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the DTC stored?
- YES: Diagnose the ETACS-ECU. Refer to DIAGNOSTIC TROUBLE CODE CHART .
- NO: Go to Step 2.
- STEP 2. Check the horn relay.
Refer to HORN RELAY CHECK .
Q: Is the horn relay in good condition?
- YES: Go to Step 3.
- NO: Replace the horn relay.
- STEP 3. Voltage measurement at the horn relay connector
- Remove the relay, and measure at the relay box side.
- Measure the voltage between the horn relay connector (power supply terminal) and ground.
OK: The voltage should measure approximately 12 volts (battery positive voltage).
Q: Is the check result normal?
- YES: Go to Step 5
- NO: Go to Step 4
- STEP 4. Check of open circuit in power supply line between the fusible link and horn relay connector.
Q: Is the check result normal?
- YES: The trouble can be an intermittent malfunction (Refer to HOW TO COPE WITH INTERMITTENT MALFUNCTION ).
- NO: Repair the connector(s) or wiring harness.
- STEP 5. Check of open circuit in N.HO line between the horn relay connector and ETACS-ECU connector.
Q: Is the check result normal?
- YES: Go to Step 6.
- NO: Repair the connector(s) or wiring harness.
- STEP 6. Check of open circuit in power supply line between the horn (HI) or (LO) connector and horn relay connector.
Q: Is the check result normal?
- YES: Go to Step 7.
- NO: Repair the connector(s) or wiring harness.
- STEP 7. Check the horn (HI) or (LO) work normally.
Connect the battery as shown, and verify that the horn sounds.
Q: Does the horn (HI) or (LO) relay work normally?
- YES: Go to Step 8.
- NO: Replace the horn (HI) or (LO). go to Step 8.
- STEP 8. Retest the theft-alarm system.
Check that the theft-alarm works normally.
Q: Does the theft-alarm system work normally?
- YES: he trouble can be an intermittent malfunction (Refer to HOW TO COPE WITH INTERMITTENT MALFUNCTION ).
- NO: Replace the ETACS-ECU.