key battery CHRYSLER VOYAGER 2000 Diagnostic Manual

Symptom:
P-1491 RADIATOR FAN CONTROL RELAY CIRCUIT
When Monitored and Set Condition:
P-1491 RADIATOR FAN CONTROL RELAY CIRCUIT
When Monitored: With the ignition key on, battery voltage greater than 10 volts, and the
PCM requests the fans to be turned on.
Set Condition: An open or shorted condition is detected in the radiator fan relay control
circuit.
POSSIBLE CAUSES
FUSED B (+) CIRCUIT OPEN
RAD FAN RELAY OUTPUT CIRCUIT, 0 VOLTS TO BATTERY V
RADIATOR FAN RELAY GROUND CIRCUIT OPEN
RADIATOR FAN RELAY DEFECTIVE
RAD FAN RELAY CONTROL CIRCUIT SHORT TO GROUND
RADIATOR FAN MOTORS W/H INTERMITTENT DEFECT
RADIATOR FAN MOTORS W/H OBSERVABLE DEFECT
RADIATOR FAN RELAY CONTROL CIRCUIT OPEN
PCM DEFECTIVE (RADIATOR FAN MOTORS)
TEST ACTION APPLICABILITY
1 Ignition On
With the DRB, actuate the Radiator Fan Relay.
Are both of the Radiator Fan Motors cycling on and off?All
Ye s®Go To 2
No®Go To 4
2 Ignition On
With the DRB, actuate the Radiator Fan Relay.
Wiggle the Wiring Harness from the Relay to the PCM.
Did the wiggling interrupt the Radiator Fan Motor cycling?All
Ye s®Repair as necessary where wiggling caused the cycling to be
interrupted.
Perform Powertrain Verification Test VER-5A.
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-5A.
No®Test Complete.
203
DRIVEABILITY
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TEST ACTION APPLICABILITY
4 Ignition On
With the DRB, actuate the Radiator Fan Relay.
Using a voltmeter, the Fan Relay Output Circuit voltage at the Relay Connector.
Does the voltage cycle from below 1.0 volt to Battery voltage?All
Ye s®Repair or replace Radiator Fans or Relay to Fan Wiring as
necessary.
Perform Powertrain Verification Test VER-5A.
No®Go To 5
5 Ignition Off
Disconnect the Radiator Fan Relay Connector.
Note: Check connectors - Clean/repair as necessary.
Turn key on.
Using a Voltmeter, measure the Fused B(+) Circuit at Relay Connector.
Is the voltage above 10.0 volts?All
Ye s®Go To 6
No®Repair the open Fused B (+) Circuit (check Radiator Fan Fuse in
PDC).
Perform Powertrain Verification Test VER-5A.
6 Ignition Off
Disconnect the Radiator Fan Relay Connector.
Note: Check connectors - Clean/repair as necessary.
Using an Ohmmeter, measure the Radiator Fan Relay Ground Circuit.
Is the resistance below 5.0 ohms?All
Ye s®Go To 7
No®Repair the open Fan Relay Ground Circuit.
Perform Powertrain Verification Test VER-5A.
7 Ignition Off
Disconnect the Radiator Fan Relay Connector.
Disconnect the PCM Connector.
Note: Check connectors - Clean/repair as necessary.
Using an Ohmmeter, measure the Radiator Fan Relay Control Circuit to a good
ground.
Is the resistance below 5.0 ohms?All
Ye s®Repair the Radiator Fan Relay Control Circuit for a short to
ground.
Perform Powertrain Verification Test VER-5A.
No®Go To 8
8 Ignition Off
Disconnect the Radiator Fan Relay Connector.
Disconnect the PCM Connector.
Note: Check connectors - Clean/repair as necessary.
Using an Ohmmeter, measure the resistance of the Radiator Fan Relay Control
Circuit from the Relay to the PCM.
Is the resistance below 5.0 ohms?All
Ye s®Go To 9
No®Repair the open Radiator Fan Relay Control Circuit.
Perform Powertrain Verification Test VER-5A.
204
DRIVEABILITY
P-1491 RADIATOR FAN CONTROL RELAY CIRCUIT ÐContinued
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