Page 4025 of 4284
Symptom:
*CHECKING IAC MOTOR (2.4L)
POSSIBLE CAUSES
IAC MOTOR OPERATION
IAC DRIVER CIRCUITS OPEN
IAC MOTOR
TEST ACTION APPLICABILITY
1 Turn the ignition on.
With the DRBIIIt, monitor engine RPM.
With the DRBIIIt, set the engine speed to 1400 RPM.
Does the engine speed reach 1400 rpm?All
Ye s®The IAC Motor is operation normally
Perform POWERTRAIN VERIFICATION TEST VER - 2.
No®Go To 2
2 Turn the ignition off.
Disconnect IAC Motor harness connector.
Disconnect the PCM harness connector.
Repeat each measurement for each IAC Driver circuit.
Measure the resistance of each IAC Driver circuit between the IAC Motor harness
connector and the PCM harness connector.
Is the resistance below 5.0 ohms at all IAC Driver circuits?All
Ye s®Replace the Idle Air Control Motor.
Perform POWERTRAIN VERIFICATION TEST VER - 2.
No®Repair the IAC Driver circuit(s) for an open.
Perform POWERTRAIN VERIFICATION TEST VER - 2.
231
DRIVEABILITY - GAS
Page 4026 of 4284
Symptom:
*CHECKING IAT SENSOR
POSSIBLE CAUSES
IAT SENSOR OPERATION
IAT SENSOR
TEST ACTION APPLICABILITY
1NOTE: Do not allow more than 5 minutes delay during the removal of the
IAT sensor and measure the temperature.
Turn the ignition on.
With the DRBIIIt, read and record the IAT temperature value.
Remove the IAT sensor.
Using a temperature probe, measure the temperature inside the opening of the IAT
sensor.
Compare both temperature readings.
Are the temperature readings with 12ÉC (10ÉF) of one another?All
Ye s®The IAT sensor is operating normally.
Perform POWERTRAIN VERIFICATION TEST VER - 2.
No®Replace the IAT sensor.
Perform POWERTRAIN VERIFICATION TEST VER - 2.
232
DRIVEABILITY - GAS
Page 4027 of 4284
Symptom:
*CHECKING MAP SENSOR
POSSIBLE CAUSES
MAP SENSOR OPERATION
MAP SENSOR
TEST ACTION APPLICABILITY
1 Turn the ignition off.
Attach a vacuum gauge to a manifold vacuum source.
NOTE: If the engine will not idle, maintain a constant engine speed above
idle.
Allow the engine to idle.
With the DRBIIIt, monitor the MAP sensor vacuum.
Compare the MAP vacuum value on the DRBIIItand the vacuum reading on the
vacuum gauge.
Are the vacuum readings within 1 inch of vacuum of each other?All
Ye s®The MAP sensor is operating normally.
Perform POWERTRAIN VERIFICATION TEST VER - 2.
No®Replace the MAP sensor.
Perform POWERTRAIN VERIFICATION TEST VER - 2.
233
DRIVEABILITY - GAS
Page 4028 of 4284
Symptom:
*CHECKING PCM POWER AND GROUND CIRCUITS
POSSIBLE CAUSES
PCM FUSED B+ CIRCUIT
PCM FUSED IGNITION SWITCH OUTPUT CIRCUIT
PCM GROUND CIRCUITS
TEST ACTION APPLICABILITY
1 Turn the ignition off.
Disconnect the PCM harness connector.
Using a 12-volt test light connected to ground, probe the PCM Fused B+ circuit in the
PCM harness connector.
Does the test light illuminate brightly?All
Ye s®Go To 2
No®Repair the Fused B+ circuit.
Perform POWERTRAIN VERIFICATION TEST VER-1.
2 Turn the ignition off.
Disconnect the PCM harness connector.
Turn the ignition on.
Using a 12-volt test light connected to ground, probe the PCM Fused Ignition Switch
Output circuit in the PCM harness connector.
Does the test light illuminate brightly?All
Ye s®Go To 3
No®Repair the Ignition Switch Output circuit
Perform POWERTRAIN VERIFICATION TEST VER-1.
3 Turn the ignition off.
Disconnect the PCM harness connector.
Using a 12-volt test light connected to battery voltage, probe the PCM ground circuits
in the PCM harness connector.
Does the test light illuminate brightly?All
Ye s®Test Complete.
No®Repair the PCM ground circuits.
Perform POWERTRAIN VERIFICATION TEST VER-1.
234
DRIVEABILITY - GAS
Page 4029 of 4284
Symptom:
*CHECKING RADIATOR FAN RELAY OUTPUT
POSSIBLE CAUSES
RADIATOR FAN RELAY OPERATION
GROUND CIRCUIT OPEN
RADIATOR FAN RELAY OUTPUT CIRCUIT
RADIATOR FAN ASSENBLY
TEST ACTION APPLICABILITY
1 Turn the ignition off.
Disconnect the Radiator Fan Relay harness connector.
Using a jumper wire, momentarily jumper the Fuse B+ circuit and Radiator Fan
Relay Output circuit in the Radiator Fan Relay harness connector.
Are both Fans operating?All
Ye s®The Radiator Fan System operating properly at this time.
Perform POWERTRAIN VERIFICATION TEST VER - 2.
No®Go To 2
2 Turn the ignition off.
Disconnect the Radiator Fan harness connector.
Measure both Ground circuit in the Radiator Fan Motor harness connectors to
ground.
Is the resistance below 5.0 ohms?All
Ye s®Go To 3
No®Repair the Ground circuit(s) for an open.
Perform POWERTRAIN VERIFICATION TEST VER - 2.
3 Turn the ignition off.
Disconnect the Radiator Fan Relay harness connector.
Disconnect both Radiator Fan Motor harness connectors.
Using a jumper wire, jumper the Fused B+ circuit and the Radiator Fan Output
circuit in the Radiator Fan Relay harness connector.
Measure the voltage in both Radiator Fan Motor harness connectors.
Is the voltage above 10 volts?All
Ye s®Replace the Radiator Fan Assembly.
Perform POWERTRAIN VERIFICATION TEST VER - 2.
No®Repair the Radiator Fan Relay Output circuit(s) for an open.
Perform POWERTRAIN VERIFICATION TEST VER - 2.
235
DRIVEABILITY - GAS
Page 4030 of 4284
Symptom:
*CHECKING THE A/C RELAY OUTPUT
POSSIBLE CAUSES
A/C CLUTCH RELAY OPERATION
GROUND CIRCUIT OPEN
A/C CLUTCH
FUSED B+ CIRCUIT
A/C CLUTCH OUTPUT CIRCUIT
IPM FUSE & RELAY CENTER
A/C CLUTCH RELAY
TEST ACTION APPLICABILITY
1NOTE: Ensure that the refrigerant system is properly charged. Refer to the
appropriate Service Information.
Turn the ignition on.
With the DRBIIIt, actuate the A/C Clutch Relay.
Is the A/C Clutch actuating?All
Ye s®The A/C Clutch System operating properly at this time.
Perform POWERTRAIN VERIFICATION TEST VER - 2.
No®Go To 2
2 Turn the ignition off.
Disconnect the A/C Clutch harness connector.
Measure the Ground circuit in the A/C Clutch harness connector to ground.
Is the resistance below 5.0 ohms?All
Ye s®Go To 3
No®Repair the Ground circuit for an open.
Perform POWERTRAIN VERIFICATION TEST VER - 2.
3 Disconnect the A/C Clutch harness connector.
Turn the ignition on.
With the DRBIIIt, actuate the A/C Clutch Relay.
Measure the voltage of the A/C Clutch Relay Output circuit in the A/C Clutch harness
connector.
Is the voltage above 11.0 volts?All
Ye s®Replace the A/C Clutch.
Perform POWERTRAIN VERIFICATION TEST VER - 2.
No®Go To 4
236
DRIVEABILITY - GAS
Page 4031 of 4284
TEST ACTION APPLICABILITY
4 Turn the ignition off.
Remove the A/C Clutch Relay from the IPM.
Using a 12-volt test light connected to ground, probe the Fused B+ circuit in the IPM.
Does the test light illuminate brightly?All
Ye s®Go To 5
No®Check for an open A/C Clutch fuse, repair the cause of the open
fuse. If OK, replace the IPM Fuse & Relay Center.
Perform POWERTRAIN VERIFICATION TEST VER - 2.
5 Turn the ignition off.
Disconnect the IPM C3 harness connector.
Disconnect the A/C Clutch harness connector.
Measure the resistance of the A/C Clutch Relay Output circuit between the IPM
harness connector and the A/C Clutch harness connector.
Is the resistance below 5.0 ohms?All
Ye s®Go To 6
No®Repair the A/C Clutch Relay Output circuit for an open.
Perform POWERTRAIN VERIFICATION TEST VER - 2.
6NOTE: Ensure all IPM harness connectors are connected.
Turn the ignition off.
Disconnect the A/C Clutch harness connector.
Remove the A/C Clutch Relay from the IPM.
Measure the resistance of the A/C Clutch Relay Output circuit between the IPM and
the A/C Clutch harness connector.
Is the resistance below 5.0 ohms?All
Ye s®Replace the A/C Clutch Relay.
Perform POWERTRAIN VERIFICATION TEST VER - 2.
No®Replace the IPM Fused & Relay Center.
Perform POWERTRAIN VERIFICATION TEST VER - 2.
237
DRIVEABILITY - GAS
*CHECKING THE A/C RELAY OUTPUT ÐContinued
Page 4032 of 4284
Symptom:
*CHECKING TP SENSOR
POSSIBLE CAUSES
THROTTLE POSITION SENSOR VOLTAGE ABOVE 1.5 VOLTS
THROTTLE POSITION SENSOR SWEEP
TP SENSOR
TEST ACTION APPLICABILITY
1NOTE: Ensure that the throttle and linkage is not binding and is operating
properly.
Turn the ignition on.
With the DRBIIIt, read the Throttle Position Sensor voltage.
Is the voltage above 1.5 volts?All
Ye s®Replace the Throttle Position Sensor.
Perform POWERTRAIN VERIFICATION TEST VER - 2.
No®Go To 2
2 Turn the ignition on.
With the DRBIIIt, monitor the Throttle Position Sensor voltage.
Slowly open the throttle from the idle position to the wide open throttle position.
Does voltage start at approximately 0.8 volts and go above 3.5 volts with a smooth
voltage change?All
Ye s®Throttle Position Sensor Operating normally.
Perform POWERTRAIN VERIFICATION TEST VER - 2.
No®Replace the Throttle Position Sensor.
Perform POWERTRAIN VERIFICATION TEST VER - 2.
238
DRIVEABILITY - GAS