|
|
MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS TSB Revision MULTIPORT FUEL INJECTION (MFI) 13A-69 TROUBLESHOOTING HINTS (The most • Open or shorted heated oxygen sensor (front) heater circuit, harness damage or connector • Heated oxygen sensor (front) heater failed. • ECM failed. DIAGNOSIS Required Special Tools: • MB991658: Test Harness • MB992110: Power Plant ECU Check Harness STEP 1. Check harness connector C-34 at the heated YES : Go to Step 2. Connector Inspection . Then go to Step 12. STEP 2. Check the heated oxygen sensor (front). and connect test harness special tool, MB991658, to the (2) Measure the resistance between heated oxygen sensor connector terminal No. 1 and terminal No. 2. Standard value: 4.5 − 8.0 Ω [at 20° C (68° F)] Q: Is the measured resistance between 4.5 and 8.0 Ω [at 20 ° C (68° F)]? YES : Go to Step 3. Step 12. STEP 3. Measure the power supply voltage at heated side. (2) Turn the ignition switch to the "ON" position. • Voltage should be battery positive voltage. (4) Turn the ignition switch to the "LOCK" (OFF) position. present? AK604492AB MB991658 Heated oxygen AK604172 2 1 C-34 harness AH |