DaimlerChrysler SPRINTER2006 Service Manual page 166

24 - 4 HEATING & AIR CONDITIONING
(4) With the A/C compressor clutch engaged, duct
temperature should not be less than 2° C (35° F) or
more than 12° C (54° F). The compressor clutch may
cycle, depending upon the ambient temperature and
humidity. If the clutch cycles, use the readings
obtained before the clutch disengaged.
(5) If the A/C compressor clutch has not cycled off
and the duct temperature is less than 2° C (35° F),
check the evaporator temperature sensor and circuit
Condition
Rapid A/C compressor clutch
cycling (ten or more cycles
per minute).
Equal pressures, but the
compressor clutch does not
engage.
Normal pressures, but A/C
Performance Test air temper-
atures at center panel outlet
are too high.
A/C SYSTEM DIAGNOSIS
Possible Causes
Very low refrigerant system
charge.
1. No refrigerant in the refrig-
erant system.
2. Faulty fuse.
3. Faulty A/C compressor
clutch coil.
4. Improperly installed or faulty
evaporator temperature sensor.
5. Faulty A/C pressure trans-
ducer.
6. Faulty engine Control Mod-
ule (ECM).
1. Excessive refrigerant oil in
system.
2. Blend door cable improperly
installed or faulty.
3. Blend-air door(s) inoperative
or sealing improperly.
by performing the ATC Function Test (Refer to 24 -
HEATING & AIR CONDITIONING - DIAGNOSIS
AND TESTING - ATC FUNCTION TEST).
(6) If the air outlet temperature fails to meet the
specifications, refer to the A/C System Diagnosis
chart.
See Refrigerant System Leaks in this group.
Test the refrigerant system for leaks. Repair,
evacuate and charge the refrigerant system, if
required.
1. See Refrigerant System Leaks in this
group. Test the refrigerant system for leaks.
Repair, evacuate and charge the refrigerant
system, if required.
2. Check the fuses in the Power distribution
block and junction block. Repair the shorted
circuit or component and replace the fuses, if
required. Refer to Group 8.
3. See A/C Compressor Clutch Coil in this
group. Test the compressor clutch coil and
replace, if required.
4. See Evaporator Temperature Sensor in this
group. Test the sensor and replace, if re-
quired.
5. See A/C Pressure Transducer in this
group. Test the sensor and replace, if re-
quired.
6. Refer to Group 9 - Engine Electrical Diag-
nostics for testing of the ECM. Test the ECM
and replace, if required.
1. See Refrigerant Oil Level in this group.
Recover the refrigerant from the refrigerant
system and inspect the refrigerant oil content.
Restore the refrigerant oil to the proper level,
if required.
2. See Mode Door Cables in this group. In-
spect the cable for proper operation and re-
place, if required.
3. See HVAC Housing in this group. Inspect
the blend-air door(s) for proper operation and
sealing. Repair if required.
Correction
VA