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Home >> Mitsubishi >> 1999 >> Galant ES V6-3.0L SOHC >> Repair and Diagnosis >> Instrument Panel, Gauges and Warning Indicators >> Testing and Inspection >> Symptom Related Diagnostic Procedures >> Symptom Diagnostic Procedures >> 2. Tachometer Does Not Work

2. Tachometer Does Not Work







CIRCUIT OPERATION
- The tachometer power is supplied from the ignition switch circuit.
- For vehicles with 2.4L engine, the tachometer detects the ignition signal by the engine control module via the ignition failure sensor.
- For vehicles with 3.0L engine, the tachometer detects the ignition signal control via the distributor.

TECHNICAL DESCRIPTION (COMMENT)
The ignition signal may not be sent from the engine, or there may be a malfunction in the power supply or ground circuit.

TROUBLESHOOTING HINTS
- Malfunction of the tachometer
- Damaged harness wire or connector

DIAGNOSIS




STEP 1. Check the input signal from the engine control.
1. Remove the combination meter.
2. Measure at the harness side of combination meter connector C-30.
3. Start the engine and allow it to idle.
4. Measure voltage between terminal number 15 and body ground.
- Voltage should be approximately 5 volts. If approximately 5 volts, go to step 4.
If not approximately 5 volts, go to Step 2.




STEP 2. Check harness connector C-30 at the combination meter connector for damage.
If harness connector C-30 is damaged, repair or replace it.
Refer to Harness Connector Inspection. If harness connector C-30 is in good condition, go to Step 3.







STEP 3. Check harness wires between combination meter connector C-30 and intermediate connector C-17.
If the harness wires between combination meter connector C-30 and intermediate connector C-17 are damaged, repair them. Check that the malfunction is eliminated.
If the harness wires are in good condition, go to Step 4.




STEP 4. Check the power supply circuit from the battery to the combination meter.
1. Remove the combination meter.
2. Measure at the harness side of combination meter connector C-30.
3. Measure voltage between terminal number 1 and ground.
- Voltage should be approximately 12 volts (battery positive voltages).
If approximately 12 volts, go to Step 7.
If not approximately 12 volts, go to Step 5.




STEP 5. Check harness connector C-30 at the combination meter connector for damage.
If harness connector C-30 is damaged, repair or replace it.
Refer to Harness Connector Inspection. If harness connector C-30 is in good condition, go to Step 6.




STEP 6. Check the harness wires between combination meter connector C-30 and the battery
If the harness wires between combination meter connector C-30 and battery are damaged, repair them.
Check that the malfunction is eliminated.
If the harness wires are in good condition, go to Step 7.












NOTE: After inspecting intermediate connector C-66, junction block connectors C-84, C-78 and joint connector C-57, inspect the wires. If intermediate connector C-66, junction block connectors C-84, C-78 and joint connector C-57 are damaged, repair or replace them. Refer to Harness Connector Inspection.




STEP 7. Check the power supply from the ignition switch to the combination meter.
1. Measure at the harness side of combination meter connector C-29.
2. Measure voltage between the terminal number 29 and ground.
- Voltage should be approximately 12 volts (battery positive voltage).
If approximately 12 volts, check that the malfunction is eliminated.
If not approximately 12 volts, go to Step 8.




STEP 8. Check harness connector C-29 at the combination meter for damage.
If harness connector C-29 is damaged, repair or replace it.
Refer to Harness Connector Inspection.
If harness connector C-29 is in good condition, go to Step 9.




STEP 9. Check the harness wires between combination meter connector C-29 and ignition switch (IG1).
If the harness wires between combination meter connector C-29 and ignition switch (IG1) are damaged, repair them.
Check that the malfunction is eliminated.
If the harness wires are in good condition, go to Step 10.






NOTE: After inspecting junction block connectors C-73 and C-78, inspect the wires. If junction block connectors C-73 and C-78 are damaged, repair or replace them. Refer to Harness Connector Inspection.




STEP 10. Check the combination meter ground circuit.
1. Measure at the harness side of combination meter connector C-29.
2. Measure continuity between terminal number 30 and body ground.
- There should be continuity (0 ohm). If there is continuity, go to step 12. If there is no continuity, go to Step 11.




STEP 11. Check the harness wires between combination meter connector C-29 and body ground.
If the harness wires between combination meter connector C-29 and ignition switch (IG1) are damaged, repair them.
Then go to Step 12.
If the harness wires are in good condition, replace the tachometer, to Check that the malfunction is eliminated.

STEP 12. Check Symptoms
Confirm that the tachometer needle works normally.
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