Mitsubishi Montero (2004+). Manual — part 632
AUTO A/C DIAGNOSIS
TSB Revision
AUTOMATIC AIR CONDITIONING
55B-17
DTC 21, 22: A/C sensor System
.
DTC SET CONDITION
• DTC 21 is set if there is a defective connector
connection, or if there is an open circuit in the
harness.
• DTC 22 is set if there is a short circuit in the A/C
sensor input circuit.
.
TROUBLESHOOTING HINT
• Malfunction of connector.
• Malfunction of the harness.
• Malfunction of the A/C sensor.
• Malfunction of the A/C-ECU.
DIAGNOSIS
Required Special Tools:
• MB991223: Harness Set
• MB991958: Scan Tool (MUT-III Sub Assembly)
• MB991824: Vehicle Communication Interface (V.C.I.)
• MB991827: MUT-III USB Cable
• MB991911: MUT-III Main Harness B (Vehicles without
CAN communication system)
A/C SENSOR
A/C-ECU
SIGNAL INPUT
CIRCUIT
Air Thermo Sensor Circuit
AC001535AF
CONNECTORS: D-21, D-24
D-21
D-24
AUTO A/C DIAGNOSIS
TSB Revision
AUTOMATIC AIR CONDITIONING
55B-18
STEP 1. Using scan tool MB991958, check data list item 21:
Air thermo sensor.
CAUTION
To prevent damage to scan tool MB991958, always turn the
ignition switch to the "LOCK" (OFF) position before con-
necting or disconnecting scan tool MB991958.
Check the data list.
Item 21: Air thermo sensor
Q: Are the evaporator blowout temperature and indicated
temperature on scan tool MB991958 almost equal?
YES : It can be assumed that this malfunction is intermittent
(Refer to GROUP 00 - How to Cope with Intermittent
Malfunction).
NO : Go to Step 2.
STEP 2. Check the A/C sensor.
When the resistance between the sensor terminals is mea-
sured at two or more temperature conditions, the resistance
should satisfy the value shown in the illustration.
NOTE: The temperature conditions at the check shall be within
the range shown in the characteristic diagram.
Q: Is the check result normal?
YES : Go to Step 3.
NO : Replace the A/C sensor. Then go to Step 5.
AC307591 AB
MB991911
DATA LINK
CONNECTOR
MB991824
MB991827
AC204170
CONNECTOR : D-21
CN
1
2
HARNESS
SIDE
AC001043
RESISTANCE k
Ω
8
6
4
2
0
-10
0
10
20
30
40
TEMPERATURE ˚C(˚F)
AB
(14)
(32)
(50)
(86)
(104)
(68)
AUTO A/C DIAGNOSIS
TSB Revision
AUTOMATIC AIR CONDITIONING
55B-19
STEP 3. Check A/C sensor connector D-21 and A/C-ECU
connector D-24 for damage.
Q: Is A/C sensor connector D-21 and A/C-ECU connector
D-24 in good condition?
YES : Go to Step 4.
NO : Repair or replace the connector. Refer to GROUP
00E, Harness Connector Inspection
. Then go
to Step 5.
STEP 4. Check the wiring harness between A/C sensor
connector D-21 (terminals 1 and 2) and A/C-ECU D-24
(terminals 30 and 29).
Q: Is the wiring harness between A/C sensor connector
D-21 (terminals 1 and 2) and A/C-ECU D-24 (terminals 30
and 29) in good condition?
YES : Replace the A/C-ECU (Refer to
). Then go
to Step 5.
NO : Repair the wiring harness. Then go to Step 5.
AC204188
CONNECTORS : D-21, D-24
D-24(B)
D-24(B)
BZ
D-21
D-21
HARNESS SIDE
HARNESS SIDE
22
23
30
31
25
26
33
34
32
24
28
3635
27
29
21
1
2
AC204188
CONNECTORS : D-21, D-24
D-24(B)
D-24(B)
BZ
D-21
D-21
HARNESS SIDE
HARNESS SIDE
22
23
30
31
25
26
33
34
32
24
28
3635
27
29
21
1
2
AUTO A/C DIAGNOSIS
TSB Revision
AUTOMATIC AIR CONDITIONING
55B-20
STEP 5. Recheck for diagnostic trouble code.
Q: Is DTC 21 or 22 set?
YES : Return to Step 1.
NO : The procedure is complete.
DTC 31: Potentiometer System of Air Mixing Damper Control Motor Assembly
.
DTC SET CONDITION
DTC 31 is output if there is an open or short circuit in
the potentiometer input circuit, or if there is an open
circuit in the power circuit or earth circuit.
.
TROUBLESHOOTING HINT
• Malfunction of connector.
• Malfunction of the harness.
• Malfunction of the air mixing damper control
motor and potentiometer.
• Malfunction of the A/C-ECU.
Air Mix Damper Motor Potentiometer Circuit
AC001535 AH
D-20
D-24
CONNECTORS: D-20, D-24
Нет комментариевНе стесняйтесь поделиться с нами вашим ценным мнением.
Текст