2000 CHRYSLER VOYAGER air conditioning

Symptom:
P-0645 A/C CLUTCH RELAY CIRCUIT
When Monitored and Set Condition:
P-0645 A/C CLUTCH RELAY CIRCUIT
When Monitored: With the ignition key on and battery voltage greater than 10 volts.
Set Condition: An open or shorted condition is detected in the A/C clutch relay control
circuit.
POSSIBLE CAUSES
FUSED IGNITION SWITCH OUTPUT CIRCUIT OPEN
AIR CONDITIONING CLUTCH RELAY DEFECTIVE
A/C CLUTCH RELAY CIRCUIT WITHOUT INTER DEFECT
A/C CLUTCH RELAY CIRCUIT WITHOUT OBSER DEFECT
A/C CLUTCH RELAY CONTROL CIRCUIT SHORT TO GROUND
AIR CONDITIONING CLUTCH RELAY CONTROL CIRCUIT OPEN
PCM DEF (A/C CLUTCH RELAY)
TEST ACTION APPLICABILITY
1 Ignition On, Engine Not Running
Actuate the Air Conditioning Clutch Relay.
Is the Air Conditioning Clutch Relay clicking?All
Ye s®Go To 2
No®Go To 4
2 Ignition On, Engine Not Running
Actuate the Air Conditioning Clutch Relay.
Wiggle the Wiring Harness from the Relay to the PCM.
Did the wiggling interrupt the clicking?All
Ye s®Repair as necessary where wiggling caused the clicking to be
interrupted.
Perform Powertrain Verification Test VER-2A.
No®Go To 3
3 Ignition Off
Using the schematic as a guide, inspect the Wiring and Connectors.
Were any problems found?All
Ye s®Repair as necessary.
Perform Powertrain Verification Test VER-2A.
No®Test Complete.
170
DRIVEABILITY
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TEST ACTION APPLICABILITY
4 Ignition Off
Remove the Air Conditioning Clutch Relay.
Note: Check connectors - Clean/repair as necessary.
Using a Voltmeter, measure the Fused Ignition Switch Output Circuit.
Is the voltage above 10.0 volts?All
Ye s®Go To 5
No®Repair the open Fused Ignition Switch Output Circuit.
Perform Powertrain Verification Test VER-2A.
5 Ignition Off
Remove the Air Conditioning Clutch Relay.
Note: Check connectors - Clean/repair as necessary.
Using an ohmmeter, measure the resistance between terminals C (85) and A (86) of
the Air Conditioning Clutch Relay.
Is the resistance below between 50 to 90 ohms?All
Ye s®Go To 6
No®Replace the Air Conditioning Clutch Relay.
Perform Powertrain Verification Test VER-2A.
6 Ignition Off
Disconnect the PCM grey connector.
Note: Check connectors - Clean/repair as necessary.
Using an Ohmmeter, measure the A/C Clutch Control Circuit from the PCM
connector to ground.
Is the resistance below 5.0 ohms?All
Ye s®Repair the Air Conditioning Clutch Relay Control Circuit for a
short to ground.
Perform Powertrain Verification Test VER-2A.
No®Go To 7
7 Ignition Off
Disconnect the PCM grey connector.
Remove the Air Conditioning Clutch Relay.
Note: Check connectors - Clean/repair as necessary.
Using an ohmmeter, measure the resistance of the Air Conditioning Clutch Relay
Control Circuit from the relay to the PCM.
Is the resistance below 5.0 ohms?All
Ye s®Go To 8
No®Repair open Air Conditioning Clutch Relay Control Circuit.
Perform Powertrain Verification Test VER-2A.
8 Ignition Off
If there are no potential causes remaining, the PCM is assumed to be defective.
View repair options.All
Repair
Replace the PCM.
Perform Powertrain Verification Test VER-2A.
171
DRIVEABILITY
P-0645 A/C CLUTCH RELAY CIRCUIT ÐContinued
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Symptom:
P-1598 A/C PRESSURE SENSOR VOLTS TOO HIGH
When Monitored and Set Condition:
P-1598 A/C PRESSURE SENSOR VOLTS TOO HIGH
When Monitored: With the ignition on, the engine running, and the A/C relay energized.
Set Condition: The A/C pressure sensor signal at PCM cavity 42 goes above 4.9 volts.
POSSIBLE CAUSES
AIR CONDITIONING PRESSURE SENSOR GROUND CIRCUIT OPEN
AIR CONDITIONING PRESSURE SENSOR DEFECTIVE
A/C PRESS SENSOR CONN AND WIRING HARN INTER DAMAGE
A/C PRESSURE SENSOR CONNECTOR AND HARNESS OBSERVABLE DEFECT
A/C PRESSURE SENSOR SIGNAL CIRCUIT OPEN
A/C PRESSURE SENSOR SIGNAL SHORT TO VOLTAGE
PCM DEFECTIVE
TEST ACTION APPLICABILITY
1 Ignition On, Engine Not Running
With the DRB, read the A/C Pressure Sensor voltage.
Is the A/C Pressure Sensor voltage above 4.6 volts?All
Ye s®Go To 2
No®Go To 7
2 Ignition Off
Disconnect the A/C Pressure Sensor.
Note: Check connectors - Clean/repair as necessary.
Turn ignition on.
Using a Voltmeter, measure voltage of the A/C Pressure Signal Circuit to ground.
Is the voltage above 6.0 volts?All
Ye s®Repair A/C Pressure Sensor Signal shorted to voltage.
Perform Powertrain Verification Test VER-2A.
No®Go To 3
214
DRIVEABILITY
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