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Speedometer does not Work.

Speedometer Circuit:

Connectors:

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 harness wires or connectors

DIAGNOSIS

Required Special Tools:
- MB991223: Harness Set
- MB991502: Scan Tool (MUT-II)

CAUTION: To prevent damage to scan tool always turn the ignition switch to "LOCK" (OFF) position before connecting or disconnecting scan tool.

STEP 1. Check the speedometer.
1. Connect scan tool MB991502 to the data link connector.
2. Use scan tool MB991502 to enter a simulated vehicle speed.

Q: Dose the speedometer correspond with the simulated vehicle speed?

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 output?

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-101.
1. Disconnect the combination meter connector C-101.
2. Turn the ignition switch to "ON"position.

3. Measure the voltage between terminal 52 and ground.

Q: Is the voltage 12 volts (battery positive voltage) between terminal 52 and ground?

YES: Go to Step 7.
NO: Go to Step 5.

STEP 5. Check the combination meter connector C-101 for damage.

Q: Is combination meter connector C-101 in good condition?

YES: Go to Step 6.
NO: Repair or replace it. Refer to Harness Connector Inspection. The speedometer should work normally.

STEP 6. Check the harness wires between combination meter connector C-101 and ignition switch (IG1).

NOTE: After checking junction block connectors C-311 and C-308, check the wires. If junction block connectors C-311 and C-308 are damaged, repair or replace them. Refer to Harness Connector Inspection.

Q: Is the harness wires between combination meter connector C-101 and ignition switch (IG1) in good condition?

YES: There is no action to be taken.
NO: Repair them. The speedometer should work normally.

STEP 7. Check the combination meter (speedometer) ground circuit at the combination meter connector C-102.
1. Disconnect the combination meter connector C-102.
2. Measure the resistance between terminal 34 and ground.

Q: Is the resistance value less than 2 ohm?

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-102 for damage.

Q: Is combination meter connector C-102 in good condition?

YES: Go to Step 9.
NO: Repair or replace it. Refer to Harness Connector Inspection. The speedometer should work normally.

STEP 9. Check the harness wire between combination meter connector C-102 and ground.

Q: Is the harness wire between combination meter connector C-102 and ground in good condition?

YES: There is no action to be taken.
NO: Repair it. The speedometer should work normally.

STEP 10. Check the combination meter vehicle speed sensor input signal circuit at the combination meter connector C-102.
1. Disconnect the vehicle speed sensor connector B-109 .
2. Disconnect the combination meter connector C-102.
3. Turn the ignition switch to "ON"position.

4. Measure the voltage between terminal 30 and ground.

Q: Is the voltage approximately 5 volts?

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-102 for damage.

Q: Is combination meter connector C-102 in good condition?

YES: For M/T go to Step 12.
For A/T go to Step 22.
NO: Repair or replace it. Refer to Harness Connector Inspection. The speedometer should work normally.

STEP 12. Check the harness wires between combination meter connector C-102 and vehicle speed sensor connector B-109 .

NOTE: After checking intermediate connector B-106 , C-25, and joint connector C-140, check the wires. If intermediate connector C-25 and joint connector C-140 are damaged, repair or replace them. Refer to Harness Connector Inspection.

Q: Are the harness wires between combination meter connector C-102 and vehicle speed sensor connector B-109 in good condition?

YES: There is no action to be taken.
NO: Repair them. The speedometer should work normally.

STEP 13. Check the vehicle speed sensor power supply circuit at the vehicle speed meter connector B-109 .
1. Disconnect the vehicle speed sensor connector B-109 .
2. Turn the ignition switch to "ON"position.
3. Measure the voltage between terminal 1 and ground.

Q: Is the voltage approximately 12 volts (battery positive voltage)?

YES: Go to Step 16.
NO: Go to Step 14.

STEP 14. Check the vehicle speed sensor connector B-109 damage.

Q: Is vehicle speed sensor connector B-109 in good condition?

YES: Go to Step 15.
NO: Repair or replace it. Refer to Harness Connector Inspection. The speedometer should work normally.

STEP 15. Check the harness wires between vehicle speed sensor connector B-109 and ignition switch (IG1).

NOTE: After checking junction block connectors C-311 and C-312, joint connector C- 141 and intermediate connector B-106 , C-25, check the wires. If junction block connectors C-311 and C-312, joint connector C-141 and intermediate connector B-106 , C-25 are damaged, repair or replace them. Refer to Harness Connector Inspection.

Q: Are the harness wires between vehicle speed sensor connector C-08 and ignition switch (IG1) in good condition?

YES: There is no action to be taken.
NO: Repair them. The speedometer should work normally.