Part 1 of 2

Speedometer does not Work.

Speedometer Circuit Part 1:

Speedometer Circuit Part 2:

Speedometer Circuit Part 3:

CIRCUIT OPERATION
- The ignition switch (IG1) circuit is the power source for the speedometer and vehicle speed sensor or output shaft speed sensor .
- The vehicle speed sensor or output shaft speed sensor are installed on the transaxle. Four pulses are generated with one turn of the vehicle speed sensor shaft. In case of M/T, these pulse signals are sent into the speedometer. and in case of A/T, these pulse signals are sent into the PCM and sent into the speedometer. The speedometer calculates the pulse signals, and operates the indicator. At the same time, the travel distance is calculated.

TECHNICAL DESCRIPTION (COMMENT)
The cause may be a faulty vehicle speed sensor circuit system or a faulty speedometer. Vehicle speed sensor is also used by the engine control module (ECM) or powertrain control module (PCM) , auto-cruise control-ECU.

TROUBLESHOOTING HINTS
- Malfunction of the vehicle speed sensor or output shaft speed sensor
- Malfunction of the combination meter (printed-circuit board or speedometer and tachometer)
- Malfunction of the ECM or PCM
- Malfunction of the auto-cruise control-ECU
- Damaged wiring harness or connectors

DIAGNOSIS

Required Special Tools:
- MB991223: Harness Set
- MB991958: Scan Tool (MUT-III Sub Assembly)
- MB991824: Vehicles Communication Interface (V.C.I.)
- MB991827: MUT-III USB Cable
- MB991911: MUT-III Main Harness B (Vehicles without CAN communication system)

STEP 1. Check the speedometer.
Use scan tool MB991958 to enter simulated vehicle speed.

1. Connect scan tool MB991958 to the data link connector.
2. Turn the ignition switch to "ON" position.
3. Select "Interactive Diagnosis" from the start-up screen.
4. Select "System Select."
5. Choose "Meter" from the "BODY" tab.
6. Select "Simulated vehicle Speed Output."

OK: The speedometer shows that simulated vehicle speed.

Q: Is the check result satisfactory?

YES: Go to Step 2.

NO: Go to Step 4.

STEP 2. Check the vehicle speed sensor.

1. Turn the ignition switch to "ON" position.
2. Read the MFI system diagnostic trouble code.

Q: Is MFI system DTC P0500 set?

YES:
- For M/T, Go to Step 13.
- For A/T, Go to Step 22.

NO: Go to Step 3.

STEP 3. Check the odometer and trip odometer operation.

Q: Do the odometer and trip odometer work correctly?

YES: Go to Step 10.

NO: Go to Step 4.

STEP 4. Check the combination meter power supply circuit at the combination meter connector C-41.

1. Disconnect the combination meter connector C-41.
2. Turn the ignition switch to "ON" position.

3. Measure the voltage between terminal 52 and ground.
- The measured value should be 12 volts (battery positive voltage).

Q: Does the measured voltage correspond with this range?

YES: Go to Step 7.

NO: Go to Step 5.

STEP 5. Check the combination meter connector C-41 for damage.

Q: Is combination meter connector C-41 in good condition?

YES: Go to Step 6.

NO: Repair or replace the connector. Refer to Harness Connector Inspection. The speedometer should work normally.

STEP 6. Check the wiring harness between combination meter connector C-41 (terminal 52) and ignition switch (IG1).

NOTE: After checking junction block connectors C-111 and C-108, check the wires. If junction block connectors C-111 and C-108 are damaged, repair or replace the wiring harness. Refer to Harness Connector Inspection.

Q: Is the wiring harness between combination meter connector C-41 (terminal 52) and ignition switch (IG1) in good condition?

YES: There is no action to be taken.

NO: Repair the wiring harness. The speedometer should work normally.

STEP 7. Check the combination meter (speedometer) ground circuit at the combination meter connector C-42.

1. Disconnect the combination meter connector C-42.

2. Measure the resistance between terminal 34 and ground.
- The measured value should be 2 ohm or less.

Q: Does the measured resistance value correspond with this range?

YES: Repair or replace the combination meter (printed-circuit board or speedometer and tachometer). The speedometer should work normally.

NO: Go to Step 8.

STEP 8. Check the combination meter connector C-42 for damage.

Q: Is combination meter connector C-42 in good condition?

YES: Go to Step 9.

NO: Repair or replace the connector. Refer to Harness Connector Inspection. The speedometer should work normally.

STEP 9. Check the wiring harness between combination meter connector C-42 (terminal 34) and ground.

Q: Is the wiring harness between combination meter connector C-42 (terminal 34) and ground in good condition?

YES: There is no action to be taken.

NO: Repair the wiring harness. The speedometer should work normally.

STEP 10. Check the combination meter vehicle speed sensor input signal circuit at the combination meter connector C-42.

1. Disconnect the vehicle speed sensor connector B-39 .

2. Disconnect the combination meter connector C-42.
3. Turn the ignition switch to "ON" position.

4. Measure the voltage between terminal 30 and ground.
- The measured value should be between approximately 7 and 8 volts

Q: Does the measured voltage correspond with this range?

YES: Repair or replace the combination meter (printed-circuit board or speedometer and tachometer). The speedometer should work normally.

NO: Go to Step 11.

STEP 11. Check the combination meter connector C-42 and vehicle speed sensor connector B-39 (terminal 3) for damage.

Q: Are combination meter connector C-42 and vehicle speed sensor connector B-39 (terminal 3) in good condition?

YES:
- For M/T go to Step 12.
- For A/T go to Step 22.

NO: Repair or replace the connector. Refer to Harness Connector Inspection. The speedometer should work normally.

STEP 12. Check the wiring harness between combination meter connector C-42 (terminal 30) and vehicle speed sensor connector B-39 (terminal 3) .

NOTE: After checking intermediate connector B-36 , C-28, and joint connector C-77, check the wires. If intermediate connector C-28 and joint connector C-77 are damaged, repair or replace the wiring harness. Refer to Harness Connector Inspection.

Q: Are the wiring harness between combination meter connector C-42 (terminal 30) and vehicle speed sensor connector B-39 (terminal 3) in good condition?

YES: There is no action to be taken.

NO: Repair the wiring harness. The speedometer should work normally.

STEP 13. Check the vehicle speed sensor power supply circuit at the vehicle speed meter connector B-39 .

1. Disconnect the vehicle speed sensor connector B-39 .
2. Turn the ignition switch to "ON" position.

3. Measure the voltage between terminal 1 and ground.
- The measured value should be 12 volts (battery positive voltage).

Q: Does the measured voltage correspond with this range?

YES: Go to Step 16.

NO: Go to Step 14.

STEP 14. Check the vehicle speed sensor connector B-39 damage.

Q: Is vehicle speed sensor connector B-39 in good condition?

YES: Go to Step 15.

NO: Repair or replace the connector. Refer to Harness Connector Inspection. The speedometer should work normally.

STEP 15. Check the wiring harness between vehicle speed sensor connector B-39 (terminal 1) and ignition switch (IG1).

NOTE: After checking junction block connectors C-111 and C-112, joint connector C-78 and intermediate connector B-36 , C-28, check the wires. If junction block connectors C-111 and C-112, joint connector C-78 and intermediate connector B-36 , C-28 are damaged, repair or replace the wiring harness. Refer to Harness Connector Inspection.

Q: Are the wiring harness between vehicle speed sensor connector C-39 (terminal 1) and ignition switch (IG1) in good condition?

YES: There is no action to be taken.

NO: Repair the wiring harness. The speedometer should work normally.

STEP 16. Check the vehicle speed sensor ground circuit at the vehicle speed sensor connector B-39 .

1. Disconnect the vehicle speed sensor connector B-39 .

2. Measure the resistance between terminal 2 and ground.
- The measured value should be 2 ohm or less.

Q: Does measured resistance value correspond with this range?

YES: Go to Step 19.

NO: Go to Step 17.

STEP 17. Check the vehicle speed sensor connector B-39 for damage.

Q: Is vehicle speed connector B-39 in good condition?

YES: Go to Step 18.

NO: Repair or replace the connector. Refer to Harness Connector Inspection. The speedometer should work normally.

STEP 18. Check the wiring harness between vehicle speed sensor connector B-39 (terminal 2) and ground.

NOTE: After checking intermediate connector B-36 , check the wires. If intermediate connector B-36 is damaged, repair or replace the wiring harness. Refer to Harness Connector Inspection.

Q: Is the wiring harness between vehicle speed sensor connector B-39 (terminal 2) and ground in good condition?

YES: There is no action to be taken.

NO: Repair the wiring harness. The speedometer should work normally.

STEP 19. Check the vehicle speed sensor signal circuit at the vehicle speed sensor connector B-39.

1. Remove the battery and the battery case.
2. Disconnect the vehicle speed sensor connector B-39.
3. Withdraw the wiring harness side of the vehicle speed sensor connector B-39.
4. Install the battery and the battery case.
5. Turn the ignition switch to "ON"

6. Measure the voltage between terminal 3 and ground.
- The measured value should be 9 volts or more.

Q: Does the measured voltage correspond with this range?

YES: Replace the vehicle speed sensor. The speedometer should work normally.

NO: Go to Step 20.

STEP 20. Check the vehicle speed sensor connector B-39 , auto-cruise control-ECU connector C-20, ECM connector C-60 <2.4L-M/T>, C-62 <3.0L-M/T> and combination meter connector C-42.

Q: Are vehicle speed sensor connector B-39, auto-cruise control-ECU connector C-20 ECM connector C-60 <2.4L-M/T>, C-62 <3.0L-M/T> and combination meter connector C-42 in good condition?

YES: Go to Step 21.

NO: Repair or replace the connector. Refer to Harness Connector Inspection. The speedometer should work normally.

STEP 21. Check the wiring harness from vehicle speed sensor connector B-39 (terminal 3) to auto-cruise control-ECU connector C-20 (terminal 10), ECM connector C-60 (terminal 86) <2.4L-M/T>, C-62 (terminal 80) <3.0L-M/T> and combination meter connector C-42 (terminal 30).

NOTE: After checking joint connector C-77 and intermediate connector C-28,check the wires. If joint connector C-77 and intermediate connector C-28 are damaged, repair or replace the wiring harness. Refer to Harness Connector Inspection.

Q: Are the wiring harness from vehicle speed sensor connector B-39 (terminal 3) to auto-cruise control-ECU connector C-20 (terminal 10), ECM connector C-60 (terminal 86) <2.4L-M/T>, C-62 (terminal 80) <3.0L-M/T> and combination meter connector C-42 (terminal 30) in good condition?

YES: Go to Step 43.

NO: Repair the wiring harness. The speedometer should work normally.

STEP 22. Using scan tool MB991958, read the diagnostic trouble code. Check if an A/T system DTC is set.

Q: Is A/T diagnostic trouble code number "23" output?

YES: Go to Step 29.

NO: Go to Step 23.