Page 4015 of 4284
Symptom:
P1602-PCM NOT PROGRAMMED
When Monitored and Set Condition:
P1602-PCM NOT PROGRAMMED
When Monitored: Ignition key on.
Set Condition: PCM has not been programmed.
POSSIBLE CAUSES
PCM PROGRAMMED
TEST ACTION APPLICABILITY
1 Attempt to program PCM in accordance with the Service Information.
Turn the ignition on.
Start the engine.
NOTE: If the engine will not start, crank the engine over for 15 seconds.
Crank at least 2 time with the ignition switch returning to the off position
each time.
Allow the engine to reach normal operating temperature.
With the DRBIIIt, read DTCs.
Does the DTC reset?All
Ye s®Replace and program the Powertrain Control Module in accor-
dance with the Service Information.
Perform POWERTRAIN VERIFICATION TEST VER-1.
No®Test Complete.
221
DRIVEABILITY - GAS
Page 4020 of 4284
Symptom:
*CHECKING ECT SENSOR
POSSIBLE CAUSES
ECT SENSOR OPERATION
ECT SENSOR
TEST ACTION APPLICABILITY
1NOTE: The engine coolant temperature must be below 62ÉC (150ÉF).
Turn the ignition on.
With the DRBIIIt, monitor the ECT value.
Start the engine.
Does the ECT reach 82ÉC (180ÉF) and was it a smooth transition?All
Ye s®Engine Coolant Temperature sensor is operating normally.
Perform POWERTRAIN VERIFICATION TEST VER - 2.
No®Replace the Engine Coolant Temperature Sensor.
Perform POWERTRAIN VERIFICATION TEST VER - 2.
226
DRIVEABILITY - GAS
Page 4022 of 4284

TEST ACTION APPLICABILITY
2 Turn the ignition off.
WARNING: The fuel system is under a constant pressure even with the
engine off. Before testing or servicing any fuel system hose, fitting or line,
the fuel system pressure must be released.
Install a fuel pressure gauge to the fuel rail test port.
Turn the ignition on.
With the DRBIIIt, actuate the ASD Fuel System test and observe the fuel pressure
gauge.
NOTE: Fuel pressure specification is 400 KPa +/- 34 KPa (58 psi +/- 5 psi).
Choose a conclusion that best matches your fuel pressure reading.All
Below Specification
Go To 3
Within Specification
Go To 5
Above Specification
Replace the fuel filter/fuel pressure regulator.
Perform POWERTRAIN VERIFICATION TEST VER-1.
Caution: Stop All Actuations.
3 Turn the ignition off.
WARNING: The fuel system is under a constant pressure even with the
engine off. Before testing or servicing any fuel system hose, fitting or line,
the fuel system pressure must be released.
Raise vehicle on hoist, and disconnect the fuel pressure line at the fuel pump module.
Install special 5/169fuel line adapter tool #6539 between disconnected fuel line and
the fuel pump module.
Attach a fuel pressure test gauge to the9T9fitting on tool #6539.
Turn the ignition on.
With the DRBIIIt, actuate the ASD Fuel System test and observe the fuel pressure
gauge.
NOTE: Fuel pressure specification is 400 KPa +/- 34 KPa (58 psi +/- 5 psi).
Is the fuel pressure within specification now?All
Ye s®Repair/replace fuel supply line as necessary.
Perform POWERTRAIN VERIFICATION TEST VER-1.
No®Go To 4
Caution: Stop All Actuations.
4 Turn the ignition off.
WARNING: The fuel system is under a constant pressure even with the
engine off. Before testing or servicing any fuel system hose,fitting or line,
the fuel system pressure must be released.
Remove the Fuel Pump Module and inspect the Fuel Inlet Strainer.
Is the Fuel Inlet Strainer plugged?All
Ye s®Replace the Fuel Pump Inlet Strainer.
Perform POWERTRAIN VERIFICATION TEST VER-1.
No®Replace the Fuel Pump Module.
Perform POWERTRAIN VERIFICATION TEST VER-1.
228
DRIVEABILITY - GAS
*CHECKING FUEL DELIVERY ÐContinued
Page 4023 of 4284

TEST ACTION APPLICABILITY
5Note: The fuel pressure must be within specification before continuing.
Turn the ignition off.
WARNING: The fuel system is under a constant pressure even with the
engine off. Before testing or servicing any fuel system hose, fitting or line,
the fuel system pressure must be released.
Disconnect the fuel supply line at the fuel rail.
Connect fuel line adapter #6539(5/169) or #6631(3/89) to the disconnected fuel supply
line. Insert the other end of the adapter into a graduated container.
Caution: Do not operate the fuel pump for more than 7 seconds in the next
step. Fuel pump module reservoir may run empty and damage to the fuel
pump will result.
Note: Specification: A good fuel pump will deliver at least 1/4 liter (1/2 pint)
of fuel in 7 seconds.
Turn the ignition on.
With the DRBIIIt, actuate the ASD Fuel System test for 7 seconds.
Is the fuel pump capacity within specification?All
Ye s®Test Complete.
No®Check for a kinked/damaged fuel supply line between the fuel
tank and fuel rail. If OK, replace the fuel pump module.
Perform POWERTRAIN VERIFICATION TEST VER-1.
Caution: Stop All Actuations.
6 Turn the ignition off.
Disconnect the fuel pump module harness connector.
Turn the ignition on.
With the DRBIIIt, actuate the ASD Fuel System test.
Using a 12 volt test light connected to ground, probe the Fuel Pump Relay Output
circuit at the Fuel Pump Module harness connector.
Does the test light illuminate brightly?All
Ye s®Go To 7
No®Go To 9
Caution: Stop All Actuations.
7 Turn the ignition off.
Disconnect the Fuel Pump Module harness connector.
Note: Check connectors - It is critical that the connector is free from any
signs of corrosion or deformities - Clean/repair as necessary.
Using a test light connected to battery voltage, probe the Fuel Pump ground circuit
at the Fuel Pump Module harness connector.
Does the test light illuminate brightly?All
Ye s®Go To 8
No®Repair the open/high resistance in the fuel pump ground circuit.
Perform POWERTRAIN VERIFICATION TEST VER-1.
8 If there are no possible causes remaining, view repair. All
Repair
Replace the Fuel Pump Module.
Perform POWERTRAIN VERIFICATION TEST VER-1.
229
DRIVEABILITY - GAS
*CHECKING FUEL DELIVERY ÐContinued
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 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 4034 of 4284

TEST ACTION APPLICABILITY
3WARNING: KEEP CLEAR OF THE ENGINE'S MOVING PARTS.
NOTE: The conditions that set the DTC are not present at this time. The
following list may help in identifying the intermittent condition.
With the engine running at normal operating temperature, monitor the DRB
parameters related to the DTC while wiggling the wiring harness. Look for param-
eter values to change and/or a DTC to set.
Review the DRB Freeze Frame information. If possible, try to duplicate the
conditions under which the DTC was set.
Refer to any Technical Service Bulletins (TSB) that may apply.
Visually inspect the related wiring harness. Look for any chafed, pierced, pinched, or
partially broken wires.
Visually inspect the related wiring harness connectors. Look for broken, bent, pushed
out, or corroded terminals.
Were any of the above conditions present?All
Ye s®Repair as necessary
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No®Test Complete.
4 Turn the ignition off.
Remove the A/C Clutch Relay from the IPM.
Turn the ignition on.
Using a 12-volt test light connected to ground, probe the Fused Ignition Switch
circuit in the IPM.
Does the test light illuminate?All
Ye s®Go To 5
No®Go To 10
5 Turn the ignition off.
Remove the A/C Clutch Relay from the IPM.
Turn the ignition on.
Using a 12-volt test light connected to 12-volts, probe the A/C Clutch Relay circuit in
the IPM.
With the DRBIIIt, actuate the A/C Clutch Relay.
Does the test light flash on and off?All
Ye s®Replace the A/C Clutch Relay.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No®Go To 6
6 Turn the ignition off.
Disconnect the Intelligent Power Module C3 harness connector.
Turn the ignition on.
Using a 12-volt test light connected to 12-volts, probe the A/C Clutch Relay Control
circuit in the IPM harness connector.
With the DRBIIIt, actuate the A/C Clutch Relay.
Does the test light flash on and off?All
Ye s®Replace the IPM Fused & Relay Center.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No®Go To 7
240
HEATING & A/C
P0645-A/C CLUTCH RELAY CKT ÐContinued
Page 4036 of 4284

Symptom:
P1598-A/C PRESSURE SENSOR VOLTS TOO HIGH
When Monitored and Set Condition:
P1598-A/C PRESSURE SENSOR VOLTS TOO HIGH
When Monitored: Engine running. The A/C relay energized.
Set Condition: The A/C pressure sensor signal at the PCM goes above 4.92 volts.
POSSIBLE CAUSES
INTERMITTENT CONDITION
A/C PRESSURE SENSOR SIGNAL CIRCUIT SHORTED TO 5 VOLT SUPPLY CIRCUIT
A/C PRESSURE SENSOR SIGNAL CIRCUIT SHORTED TO BATTERY VOLTAGE
A/C PRESSURE SENSOR INTERNAL FAILURE
A/C PRESSURE SENSOR SIGNAL CIRCUIT OPEN
SENSOR GROUND CIRCUIT OPEN
PCM
TEST ACTION APPLICABILITY
1NOTE: Ensure the A/C refrigerant System is properly charged per the
Service Information.
Start the engine.
With the DRBIIIt, read the A/C Pressure Sensor voltage.
Is the voltage above 4.6 volts.All
Ye s®Go To 2
No®Go To 8
2 Turn the ignition off.
Disconnect the A/C Pressure Sensor harness connector.
Disconnect the PCM harness connector.
Measure the resistance between the A/C Pressure Sensor Signal circuit and the 5 Volt
Supply circuit in the A/C Pressure Sensor harness connector.
Is the resistance below 100 ohms?All
Ye s®Repair the A/C Pressure Sensor Signal circuit for a short to the 5
Volt Supply circuit.
Perform POWERTRAIN VERIFICATION TEST VER - 2.
No®Go To 3
242
HEATING & A/C