Automatic Air Conditioning -- Lancer: Diagnosis Mitsubishi Lancer IX facelift

AUTOMATIC AIR CONDITIONING TROUBLESHOOTING STRATEGY

Use these steps to plan your diagnostic strategy. If you follow them carefully, you will be sure that you have exhausted most of the possible ways to find a heater, air conditioning and ventilation fault.

1. Gather information from the customer.
2. Verify that the condition described by the customer exists.
3. Find the malfunction by following the Symptom Chart.
4. Verify malfunction is eliminated.

HOW TO CONNECT THE SCAN TOOL (M.U.T.-III)

Required Special Tools

1. MB991958: Scan Tool (M.U.T.-III Sub Assembly) MB991824: Vehicle Communication Interface (V.C.I.) MB991827: M.U.T.-III USB Cable MB991910: M.U.T.-III Main Harness A (Vehicles with CAN communication system)

1. Ensure that the ignition switch is at the "LOCK" (OFF) position.
2. Start up the personal computer.
3. Connect special tool MB991827 to special tool MB991824 and the personal computer.
4. Connect special tool MB991910 to special tool MB991824
5. Connect special tool MB991910 to the data link connector.
6. Turn the power switch of special tool MB991824 to the "ON" position. NOTE: When the special tool MB991824 is energized, the special tool MB991824 indicator light will be illuminated in a green color.
7. Start the M.U.T.-III system on the personal computer.

Note. Disconnecting the scan tool special tool MB991824 is the reverse of the connecting sequence, making sure that the ignition switch is at the "LOCK" (OFF) position.

HOW TO READ AND ERASE DIAGNOSTIC TROUBLE CODES

Required Special Tools

1. MB991958: Scan Tool (M.U.T.-III Sub Assembly) MB991824: Vehicle Communication Interface (V.C.I.) MB991827: M.U.T.-III USB Cable MB991910: M.U.T.-III Main Harness A (Vehicles with CAN communication system)

Note. If the battery voltage is low, diagnostic trouble codes will not be output. Check the battery if scan tool MB991958 does not display.

1. Connect the scan tool MB991958 to the data link connector.
2. Turn the ignition switch to the "ON" position.
3. Select "System select" from the start-up screen.
4. Select "From 2006 MY" of "Model Year." When the "Vehicle Information" is displayed, check the contents.
5. Select "AUTO A/C" from "System List," and press the "OK" button. NOTE: When the "Loading Option Setup" list is displayed, check the applicable item.
6. Select "Diagnostic Trouble Code".
7. If a DTC is set, it is shown.
8. Choose "Erase DTCs" to erase the DTC.

HOW TO PERFORM ACTUATOR TEST

Required Special Tools

1. MB991958: Scan Tool (M.U.T.-III Sub Assembly) MB991824: Vehicle Communication Interface (V.C.I.) MB991827: M.U.T.-III USB Cable MB991910: M.U.T.-III Main Harness A (Vehicles with CAN communication system)

1. Connect the scan tool MB991958 to the data link connector.
2. Turn the ignition switch to the "ON" position.
3. Select "System Select".
4. Select "AUTO A/C" from "System List," and press the "OK" button.
5. Choose "Actuator Test" from "AUTO A/C" screen.
6. Choose an appropriate item and select the "OK" button.

HOW TO DIAGNOSE THE CAN BUS LINE

Required Special Tools

1. MB991958: Scan Tool (M.U.T.-III Sub Assembly) MB991824: Vehicle Communication Interface (V.C.I.) MB991827: M.U.T.-III USB Cable MB991910: M.U.T.-III Main Harness A

1. Connect scan tool MB991958 to the data link connector.
2. Turn the ignition switch to the "ON" position.
3. Select "CAN bus diagnosis" from the start-up screen.
4. When the vehicle information is displayed, confirm that it matches the vehicle whose CAN bus lines will be diagnosed. If they match, go to step 8 . If not, go to step 5.
5. Select "view vehicle information" button.
6. When the vehicle information is displayed, confirm again that it matches the vehicle which is diagnosed CAN bus line. If they match, go to step 8 . If not, go to step 5 .
7. Press the "OK" button.
8. When the options are displayed, choose the options (mark the check) and then select "OK".

DIAGNOSTIC TROUBLE CODE CHART

DIAGNOSTIC TROUBLE CODE CHART

Scheme 98

DTC SET CONDITION

1. DTC B10C0 is set if there is a short circuit in the interior temperature sensor input circuit.
2. DTC B10C1 is set if there is a defective connector connection, or if there is an open circuit in the harness.

Current trouble

1. The A/C-ECU, the interior temperature sensor, or connector(s) or wiring between the two may be defective.

Past trouble

1. If DTC B10C0 or B10C1 is stored as a past trouble, carry out diagnosis with particular emphasis on wiring and connector(s) between the A/C-ECU and the interior temperature sensor. If the connectors and wiring are normal, and obviously the ECU is the cause of the trouble, replace the ECU. If in doubt, do not replace the ECU.

TROUBLESHOOTING HINT

1. Malfunction of connector.
2. Malfunction of the harness.
3. Malfunction of the interior temperature sensor.
4. Malfunction of the A/C-ECU.

DIAGNOSIS

Required Special Tool

1. MB991958: Scan Tool (M.U.T.-III Sub Assembly) MB991824: Vehicle Communication Interface (V.C.I.) MB991827: M.U.T.-III USB Cable MB991910: M.U.T.-III Main Harness A

Scheme 99

1. 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. Use scan tool MB991958 to diagnose the CAN bus lines. Connect scan tool MB991958. Refer to " «HOW TO CONNECT THE SCAN TOOL (M.U.T.-III)»(ref-291277-S31542535062008072500000) ". Turn the ignition switch to "ON" position. Diagnose the CAN bus line. Q: Is the check result satisfactory? YES : Go to Step 2 . NO : Repair the CAN bus lines. Repair the CAN bus lines (Refer to «DIAGNOSIS-CAN BUS DIAGNOSTIC CHART»(ref-291274-S15618687652008072500000) ).
2. STEP 2. Recheck for diagnostic trouble code . Recheck if the DTC is set. Erase the DTC. Turn the ignition switch to "ON" position. Check if the DTC is set. Q: Is the check result satisfactory? YES : It can be assumed that this malfunction is intermittent. «HOW TO COPE WITH INTERMITTENT MALFUNCTIONS»(ref-291250-S25713329702008072500000) . NO : Go to Step 3 .
3. STEP 3. Check interior temperature sensor connector C-08 and A/C-ECU connector C-20 for loose, corroded or damaged terminals, or terminals pushed back in the connector . Q: Are interior temperature sensor connector C-08 and A/C-ECU connector C-20 in good condition? YES : Go to Step 4 . NO : Repair or replace the connector. Refer to «HARNESS CONNECTOR INSPECTION»(ref-291251-S32776583382008072500000) .
4. STEP 4. Check the wiring harness between A/C-ECU connector C-20 (terminal 17 and 19) and interior temperature sensor connector C-08 (terminals 1 and 2) . NOTE: Also check joint connector C-02 for loose, corroded, or damaged terminals, or terminals pushed back in the connector. If joint connector C-02 is damaged, repair or replace the connector as described in «HARNESS CONNECTOR INSPECTION»(ref-291251-S32776583382008072500000) . Q: Is the wiring harness between A/C-ECU connector C-20 (terminal 17 and 19) and interior temperature sensor connector C-08 (terminals 1 and 2) in good condition? YES : Go to Step 5 . NO : Repair the wiring harness.
5. STEP 5. Check the interior temperature sensor . Measure the resistance between connector terminals 1 and 2 under at least two different temperatures. The resistance values should generally match those in the graph. NOTE: The temperature at the check should not exceed the range in the graph. Q: Is the interior temperature sensor in good condition? YES : Replace the A/C-ECU. Then go to Step 6 . NO : Replace the interior temperature sensor. Then go to Step 6 .
6. STEP 6. Recheck for diagnostic trouble code . Check again if the DTC is set. Connect scan tool MB991958 to the data link connector Turn the ignition switch to the "ON" position. Check if the DTC is set. Turn the ignition switch to the "LOCK" (OFF) position. Q: Is the check result satisfactory? YES : The procedure is complete. NO : Return to Step 1 .

SYMPTOM CHART

SYMPTOM CHART

Scheme 100

TROUBLESHOOTING HINTS

1. Malfunction of the photo sensor
2. Malfunction of the A/C-ECU
3. Malfunction of connector.
4. Malfunction of the harness.

Required Special Tools

1. MB991223: Harness Set
2. MB992006: Extra Fine Probe
3. 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

1. STEP 1. Check the defogger and outside/inside air selection damper control motor operation . Q: Do the defogger and outside/inside air selection damper control motor work normally? YES : Go to Step 2 . NO : Refer to «SYMPTOM CHART»(ref-291276-S24932584132008072500000) .
2. STEP 2. Using scan tool MB991958, read the diagnostic trouble code . 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. Check if an A/C-ECU DTC is set. Connect scan tool MB991958 to the data link connector. Turn the ignition switch to the "ON" position. Check if the DTC is set. Turn the ignition switch to the "LOCK" (OFF) position. Q: Is the check result satisfactory? YES : Go to Step 3 . NO : Refer to «HOW TO DIAGNOSE THE CAN BUS LINE»(ref-291277-S22953683412008072500000) .
3. STEP 3. Using scan tool MB991958, check data list . Connect scan tool MB991958 to the data link connector. Start the engine. Set scan tool MB991958 to the data reading mode. Item 67: Photo sensor Cover the photo sensor and security indicator with your hand or a shop towel. NOTE: Check that the voltage displayed on the scan tool changes. Turn the ignition switch to the "LOCK" (OFF) position. Q: Does the voltage displayed on the scan tool change when the photo sensor and security indicator is covered? YES : Replace the A/C-ECU. Check that the A/C works normally. NO : Go to Step 4 .
4. STEP 4. Check A/C-ECU connector C-20 and photo sensor connector C-101 for loose, corroded or damaged terminals, or terminals pushed back in the connector . Q: Are A/C-ECU connector C-20 and photo sensor connector C-101 in good condition? YES : Go to Step 5 . NO : Repair or replace the connector. Refer to «HARNESS CONNECTOR INSPECTION»(ref-291251-S32776583382008072500000) .
5. STEP 5. Check the wiring harness between photo sensor connector C-101 (terminals 4 and 1) and A/C-ECU connector C-20 (terminals 19 and 18) . Q: Is the wiring harness between photo sensor connector C-101 (terminals 4 and 1) and A/C-ECU connector C-20 (terminals 19 and 18) in good condition? YES : Go to Step 6 . NO : Repair the wiring harness. Check that the A/C works normally.
6. STEP 6. Replace the photo sensor . Q: Does the A/C operate normally? YES : No action is necessary and testing is complete. NO : Replace the A/C-ECU. Check that the A/C works normally.

ACTUATOR TEST

ACTUATOR TEST REFERENCE

Scheme 101

C-20 AND C-19 CONNECTOR TERMINAL REFERENCE