DaimlerChrysler Jeep Grand Cherokee 2002, Service Manual

Page: 223 / 284

Symptom:
*A/C OPERATES IN ALL MODE SWITCH POSITIONS
POSSIBLE CAUSES
CHECK FOR ECM DTCS
A/C CLUTCH
A/C CLUTCH RELAY OUTPUT CIRCUIT SHORTED TO VOLTAGE
A/C CLUTCH RELAY
ENGINE CONTROL MODULE
A/C SWITCH SIGNAL CIRCUIT SHORTED TO GROUND
AZC MODULE OR A/C - HEATER CONTROL MODULE
BODY CONTROL MODULE
TEST ACTION APPLICABILITY
1 With the DRBIII
t
, check for ECM DTCs.
Are any DTCs present?
All
Yes
→
Return to the symptom list and choose the symptom(s).
Perform ROAD TEST VERIFICATION - VER-2.
No
→
Go To 2
2 Turn the ignition on.
Position the Mode switch on the AZC Module or the A/C - Heater Control Module to
the Panel position.
Turn the A/C Select switch off.
With the DRBIII
t
in BCM, select Inputs/Outputs.
Monitor the A/C Select Switch state while turning the A/C Select switch from off to
on and then back to off.
Does the switch state change from Off to On and then back to Off?
All
Yes
→
Go To 3
No
→
Go To 6
3 Turn the ignition off.
Disconnect the A/C Clutch harness connector.
WARNING: WHEN THE ENGINE IS OPERATING, DO NOT STAND IN A
DIRECT LINE WITH THE FAN. DO NOT PUT YOUR HANDS NEAR THE
PULLEYS, BELTS OR FAN. DO NOT WEAR LOOSE CLOTHING.
Start the engine and observe the A/C Clutch and Compressor.
Does the A/C Compressor run with the harness connector disconnected? All
Yes
→
Replace the A/C Clutch in accordance with the Service Informa-
tion.
Perform ROAD TEST VERIFICATION - VER-2.
No
→
Go To 4
215
DRIVEABILITY - DIESEL
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