Inspection Procedure 3
INSPECTION PROCEDURE 3: Outside/Inside Air Changeover is not possible.Outside/Inside Air Selection Motor Circuit (Part 1):
Outside/Inside Air Selection Motor Circuit (Part 2):
CIRCUIT OPERATION
If the outside/inside air selection damper control motor does not operate normally, the outside/inside air selection damper control motor system may be defective.
TROUBLESHOOTING HINTS
- Malfunction of the outside/inside air selection damper control motor
- Malfunction of the A/C-ECU
- Damaged harness wires or connectors
DIAGNOSIS
Required Special Tools:
- MB991223:: Harness Set
- MB992006: Extra Fine Probe
STEP 1. Check the defogger and A/C operations.
Q: Do the defogger and A/C work normally?
YES : Go to Step 2.
NO : Refer to Inspection procedure 10 "Malfunction of the A/C-ECU power supply system." Inspection Procedure 10
STEP 2. Check outside/inside air selection damper control motor connector C-106 for loose, corroded or damaged terminals, or terminals pushed back in the connector.
Q: Is outside/inside air selection damper control motor connector C-106 in good condition?
YES : Go to Step 3.
NO : Repair or replace the connector. Check that the outside/inside air selection damper control motor works normally.
STEP 3. Measure the voltage at outside/inside air selection damper control motor connector C-106.
1. Disconnect outside/inside air selection damper control motor connector C-106, and measure the voltage at the harness side.
2. Turn the ignition switch to the "ON" position.
3. Measure the voltage between terminal 1 and ground.
- The measured value should be approximately 12 volts (battery positive voltage).
Q: Does the measured voltage correspond with this range?
YES : Go to Step 5.
NO : Go to Step 4.
STEP 4. Check the wiring harness between outside/inside air selection damper control motor connector C-106 (terminal 1) and the ignition switch (IG2).
NOTE: Also check joint connector C-03, junction block connectors C-211 and C-215 for loose, corroded, or damaged terminals, or terminals pushed back in the connector. If intermediate connector C-03, junction block connector C-211 or C-215 is damaged, repair or replace the connector as described.
Q: Is the wiring harness between outside/inside air selection damper control motor connector C-106 (terminal 1) and the ignition switch (IG2) in good condition?
YES : It can be assumed that this malfunction is intermittent.
NO : Repair the wiring harness. Check that the outside/inside air selection damper control motor works normally.
STEP 5. Check the outside/inside air selection damper control motor.
CAUTION: Cut off the battery voltage when the damper is in the inside/outside air position.
Check the outside/inside air selection damper control motor by the following procedures.
Q: Does outside/inside air selection damper control motor work normally?
YES : Go to Step 6.
NO : Replace the outside/inside air selection damper control motor. Check that the outside/inside air selection damper control motor works normally.
STEP 6. Check A/C-ECU connector C-15 for loose, corroded or damaged terminals, or terminals pushed back in the connector.
Q: Is A/C-ECU connector C-15 in good condition?
YES : Go to Step 7.
NO : Repair or replace the connector. Check that the outside/inside air selection damper control motor works normally.
STEP 7. Check the wiring harness between outside/inside air selection damper control motor connector C-106 (terminals 4 and 5) and A/C-ECU C-15 (terminals 5 and 6).
Q: Are the wiring harness between outside/inside air selection damper control motor connector C-106 (terminals 4 and 5) and A/C-ECU C-15 (terminals 5 and 6) in good condition?
YES : Go to Step 8.
NO : Repair the wiring harness. Check that the outside/inside air selection damper control motor works normally.
STEP 8. Retest the system.
Q: Does a malfunction take place again?
YES : Replace the A/C-ECU, and check that the outside/inside air selection damper control motor works normally.
NO : It can be assumed that this malfunction is intermittent.