Inspection Procedure 6
INSPECTION PROCEDURE 6: Speedometer does not work (other meters work).INSPECTION PROCEDURE 7: The fuel gauge needle moves excessively.
CAUTION: When the battery cable is disconnected or the combination meter is removed, the fuel gauge learned value will be erased. To let the display unit re-learn it, enter the vehicle speed (by driving the vehicle or entering simulated vehicle speed) and then stop the vehicle.
CIRCUIT OPERATION
The output shaft speed sensor sends vehicle signal to the combination meter via the ECM
TECHNICAL DESCRIPTION (COMMENT)
If only the speedometer does not operate, the ECM
TROUBLESHOOTING HINTS
- Malfunction of the combination meter
- Malfunction of the ECM
- The wiring harness or connectors may have loose, corroded, or damaged terminals, or terminals pushed back in the connector.
DIAGNOSIS
Required Special Tools:
- MB991958: Scan Tool (M.U.T.-III Sub Assembly)
- MB991824: V.C.I.
- MB991827: M.U.T.-III USB Cable
- MB991910: M.U.T.-III Main Harness A
STEP 1. Using scan tool MB991958, diagnose the CAN bus line.
CAUTION: To prevent damage to scan tool (MB991958), always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool (MB991958).
1. Connect scan tool MB991958 to the data link connector.
2. Turn the ignition switch to "ON" position.
3. Diagnose the CAN bus line.
4. Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the check result satisfactory?
YES: Go to Step 2.
NO: Repair the CAN bus lines (Refer to Information Bus, Diagnosis-Can Bus Diagnostic Chart).
STEP 2. Using scan tool MB991958, read MFI diagnostic trouble code.
Check if an MFI system diagnostic trouble code is set.
1. Turn the ignition switch to "ON" position.
2. Diagnose the CAN bus line.
3. Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the DTC set?
YES: Refer to MFI Diagnosis - Diagnostic Trouble Code Chart.
NO: Go to Step 3.
STEP 3. Using scan tool MB991958, check data list.
1. Turn the ignition switch to the "ON" position.
2. Set scan tool MB991958 to the data reading mode.
- Item 54: Speedometer (Input)
- Speedometer and M.U.T.-III displayed values agree with each other.
3. Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the measured voltage equal to battery positive voltage?
YES: It can be assumed that this malfunction is intermittent. Refer to How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunction.
NO: Go to Step 4.
STEP 4. Using scan tool MB991958, check actuator test.
Use scan tool MB991958 to enter simulated vehicle speed.
1. Turn the ignition switch to "ON" position.
2. Select "Interactive Diagnosis" from the start-up screen.
3. Select "System Select."
4. Choose "Meter" from the "BODY" tab.
5. Select "Simulated vehicle Speed Output."
OK: The speedometer shows the simulated vehicle speed.
6. Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the check result satisfactory?
YES: Go to Step 5.
NO: Replace the combination meter.
STEP 5. Retest the system.
Check that the speedometer works normally.
Q: Is the check result satisfactory?
YES: The procedure is complete. (If no malfunctions are found in all steps, an intermittent malfunction is suspected. Refer to How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunction).
NO: Replace the combination meter.