Dodge Caliber. Manual - part 720

(K299) O2 1/2 HEATER CONTROL CIRCUIT OPEN OR HIGH RESISTANCE

Disconnect the Powertrain Control Module (PCM) harness connector.

Measure the resistance of the (K299) O2 1/2 Heater Control circuit from
the Oxygen Sensor 1/2 harness connector to the Powertrain Control
Module (PCM) harness connector.

Is the resistance below 0.5 ohm?

Yes

>> Go to 4

>> Repair the (K299) O2 1/2 Heater Control circuit for an open

circuit or high resistance.

Perform the PCM Verification Test Ver. 1 (Refer to 9 -
ENGINE - DIAGNOSIS AND TESTING).

(Z924) GROUND CIRCUIT OPEN OR HIGH RESISTANCE

Using a 12 volt test light connected to 12 volts, check the (Z924)
Ground circuit in the Oxygen Sensor 1/2 harness connector.

NOTE: The test light should be illuminated and bright. Compare
the brightness to that of a direct connection to the battery.

Is the test light illuminated and bright?

Yes

>> Go to 5

>> Repair the (Z924) Ground circuit for an open circuit or high

resistance.

Perform the PCM Verification Test Ver. 1 (Refer to 9 -
ENGINE - DIAGNOSIS AND TESTING).

POWERTRAIN CONTROL MODULE (PCM)

Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Oxygen Sensor 1/2
and the Powertrain Control Module (PCM).

Look for any chafed, pierced, pinched, or partially broken wires.

Look for broken, bent, pushed out or corroded terminals.

Refer to any Technical Service Bulletins that may apply.

Were any problems found?

Yes

>> Repair as necessary.

Perform the PCM Verification Test Ver. 1 (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).

>> Replace and program the Powertrain Control Module (PCM) in accordance with the Service Information.

Perform the PCM Verification Test Ver. 1 (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).

ENGINE ELECTRICAL DIAGNOSTICS - GPEC

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P0171-FUEL SYSTEM 1/1 LEAN

For a complete wiring diagram Refer to Section 8W.

•

When Monitored:
With the engine running in closed loop, the ambient/battery temperature above 20° F (-6° C) and altitude below
8500 ft.

•

Set Condition:
If the PCM multiplies short term adaptive by long term adaptive and a certain percentage is exceeded for two
trips, a freeze frame is stored, the MIL illuminates and a DTC is set. Two Trip Fault. Three good trips to turn
off the MIL

Possible Causes

INTERMITTENT DTC

O2 SENSOR SIGNAL CIRCUIT

O2 SENSOR RETURN CIRCUIT

ECT SENSOR

MAP SENSOR

O2 SENSOR

RESTRICTED FUEL SUPPLY LINE

FUEL PUMP INLET STRAINER PLUGGED

FUEL FILTER/PRESSURE REGULATOR

FUEL PUMP MODULE

ENGINE MECHANICAL PROBLEM

POWERTRAIN CONTROL MODULE (PCM)

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 9 - ENGINE -
DIAGNOSIS AND TESTING).

Diagnostic Test

DTC IS ACTIVE

Diagnose all other trouble codes before continuing with this procedure.

NOTE: Check for contaminants that may have damaged an O2 Sensor: contaminated fuel, unapproved sil-
icone, oil and coolant.
Ignition on, engine not running.

With a scan tool, select View DTCs.

Is the status Active for this DTC?

Yes

>> Go to 2

>> Refer to the *CHECKING FOR AN INTERMITTENT DTC Diagnostic Procedure. (Refer to 9 - ENGINE -

DIAGNOSIS AND TESTING)

FUEL PRESSURE OUT OF SPECIFICATION

WARNING: The fuel system is under a constant pressure even with the engine off. Before testing or ser-
vicing any fuel system hose, fitting or line, the fuel system pressure must be released. Failure to follow
these instructions can result in personal injury or death.
Install a fuel pressure gauge on the fuel rail.

Ignition on, engine not running.

With a scan tool, actuate the fuel pump relay control and observe the fuel pressure gauge.

NOTE: Fuel pressure specification is 407 KPa +/- 34 KPa (59 psi +/- 5 psi).
Turn the ignition off.

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ENGINE ELECTRICAL DIAGNOSTICS - GPEC

CAUTION: Stop all actuation tests before continuing.

Choose a conclusion that best matches the fuel pressure reading.

Within Specification

Go to 3

Above Specification

Replace the fuel filter/pressure regulator.

Perform the PCM Verification Test Ver. 1 (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).

Below Specification

Go to 11

ENGINE COOLANT TEMPERATURE

Ignition on, engine not running.

NOTE: If necessary, allow the engine to cool to ambient temperature before proceeding.
Using the appropriate service information, determine the proper opening temperature of the thermostat.

With a scan tool, read the ECT sensor value. If the engine was allowed to cool completely, the value should be
approximately equal to the ambient temperature.

Start the engine and allow it to reach operating temperature while monitoring the ECT sensor value. The sensor
value change should be a smooth transition from start up to normal operating temperature. Also monitor the actual
coolant temperature with a thermometer.

NOTE: As the engine warms up to operating temperature, the actual coolant temperature (thermometer read-
ing) and the coolant temperature value on the scan tool should be relatively close. The thermostat should
not open until the engine reaches the temperature specified in the Service Information.

Were any problems found?

Yes

>> Repair as necessary.

Perform the PCM Verification Test Ver. 1 (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).

>> Go to 4

MAP SENSOR

Turn the ignition off.

Connect a vacuum gauge to a manifold vacuum source.

Start the engine.

Allow the engine to idle.

NOTE: If engine will not idle, maintain a constant RPM above idle.
With the scan tool, read the MAP Sensor vacuum value.

Is the scan tool reading within 1

(

of the vacuum gauge reading?

Yes

>> Go to 5

>> Replace the MAP Sensor.

Perform the PCM Verification Test Ver. 1 (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).

O2 SENSOR VOLTAGE

Start the engine.

If necessary, allow the engine to reach normal operating temperature.

With a scan tool, monitor all O2 Sensor voltage readings.

Is the voltage switching between 2.5 and 3.4 volts for all O2 sensors?

Yes

>> Go to 6

>> Go to 8

ENGINE ELECTRICAL DIAGNOSTICS - GPEC

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1/1 O2 SENSOR HEATER

Turn the ignition off.

NOTE: Wait a minimum of 10 minutes to allow the O2 Sensor to cool down before continuing the test. Allow
the O2 Sensor voltage to stabilize at 5.0 volts.
Ignition on, engine not running.

With a scan tool, actuate the 1/1 O2 Sensor heater.

With the scan tool, monitor 1/1 O2 Sensor voltage for at least 2 minutes.

Does the voltage stay above 4.5 volts?

Yes

>> Replace the 1/1 O2 Sensor.

Perform the PCM Verification Test Ver. 1 (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).

>> Go to 7

ENGINE MECHANICAL PROBLEM

Turn the ignition off.

Check for any of the following conditions/mechanical problems.

AIR INDUCTION SYSTEM - must be free from leaks.

ENGINE VACUUM - must be at least 13 inches in neutral

ENGINE VALVE TIMING - must be within specifications

ENGINE COMPRESSION - must be within specifications

ENGINE EXHAUST SYSTEM - must be free of any restrictions or leaks.

ENGINE PCV SYSTEM - must flow freely

TORQUE CONVERTER STALL SPEED - must be within specifications

POWER BRAKE BOOSTER - no internal vacuum leaks

FUEL - must be free of contamination

FUEL INJECTOR - plugged or restricted injector; control wire not connected to correct injector

Are there any engine mechanical problems?

Yes

>> Repair as necessary.

Perform the PCM Verification Test Ver. 1 (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).

>> Go to 13

O2 SENSOR

Turn the ignition off.

Disconnect the O2 Sensor harness connector for the sensor where the voltage was not switching between 2.5 and
3.4 volts.

Turn the ignition on.

With a scan tool, monitor the O2 Sensor voltage.

NOTE: The voltage should be approximately 5.0 volts with the connector disconnected.
Connect a jumper wire between the signal circuit and the return circuit in the O2 Sensor harness connector.

NOTE: The voltage should drop from 5.0 volts to 2.5 volts with the jumper wire in place.

Did the O2 Sensor voltage change as described above?

Yes

>> Replace the O2 Sensor.

Perform the PCM Verification Test Ver. 1 (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).

>> Go to 9

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