Dodge Caliber. Manual - part 887

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When Monitored:
Ignition on, engine running, and no ECT DTCs present.

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Set Condition:
The coolant temperature should change at a specific rate. If this rate is too slow or too fast this fault will set.
Two trip fault. Three good trips to clear MIL. ETC light will illuminate on first trip failure.

Possible Causes

INTERMITTENT DTC

LOW COOLANT LEVEL

THERMOSTAT

(K2) ECT 1 SIGNAL CIRCUIT SHORTED TO VOLTAGE

(K2) ECT 1 SIGNAL CIRCUIT SHORTED TO GROUND

(K2) ECT 1 SIGNAL CIRCUIT SHORTED TO (K900) SENSOR GROUND 1 CIRCUIT

(K2) ECT 1 SIGNAL CIRCUIT OPEN OR HIGH RESISTANCE

(K900) SENSOR GROUND 1 CIRCUIT OPEN OR HIGH RESISTANCE

ENGINE COOLANT TEMPERATURE SENSOR 1

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

Ignition on, engine not running.

With a scan tool, select View DTCs.

NOTE: Diagnose and repair any Engine Coolant Temperature (ECT) sensor DTCs before proceeding with
this test.

NOTE: Inspect the ECT sensor and related PCM connector terminals for corrosion or damage.

NOTE: Extremely cold ambient temperatures may cause this DTC to set.

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)

LOW ENGINE COOLANT LEVEL

Ignition on, engine not running.

WARNING: Allow the engine to cool before opening the cooling system. The system may be under pressure.
Extreme burns or scalding may result. Failure to follow these instructions can result in personal injury or
death.
Inspect the cooling system for proper coolant level and condition.

Were any problems found?

Yes

>> Inspect the vehicle for a coolant leak. Repair as necessary in accordance with the Service Information.

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

>> Go To 3

ENGINE ELECTRICAL DIAGNOSTICS - GPEC

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THERMOSTAT

Ignition on, engine not running.

NOTE: Allow the engine to cool to ambient temperature before proceeding with this test.
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. Monitor the actual cool-
ant 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.

Does the thermostat open at the temperature specified in the Service Information?

Yes

>> Go to 4

>> Replace the thermostat in accordance with the Service Information.

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

(K2) ECT 1 SIGNAL CIRCUIT SHORTED TO VOLTAGE

Turn the ignition off.

Disconnect the Engine Coolant Temperature Sensor 1 connector.

Disconnect the Powertrain Control Module (PCM) connector.

Turn the ignition on.

Measure the voltage of the (K2) ECT 1 Signal circuit in the Engine
Coolant Temperature Sensor 1 harness connector.

Is there any voltage present?

Yes

>> Repair the (K2) ECT 1 Signal circuit for a short to voltage.

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

>> Go to 5

(K2) ECT 1 SIGNAL CIRCUIT SHORTED TO GROUND

Turn the ignition off.

Measure the resistance between ground and the (K2) ECT 1 Signal cir-
cuit in the Engine Coolant Temperature Sensor 1 harness connector.

Is the resistance above 100 ohms?

Yes

>> Go to 6

>> Repair the (K2) ECT 1 Signal circuit for a short to ground.

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

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ENGINE ELECTRICAL DIAGNOSTICS - GPEC

(K2) ECT 1 SIGNAL CIRCUIT SHORTED TO (K900) SENSOR GROUND 1 CIRCUIT

Measure the resistance between the (K2) ECT 1 Signal circuit and the
(K900) Sensor Ground 1 circuit in the Engine Coolant Temperature Sen-
sor 1 harness connector.

Is the resistance above 100 ohms?

Yes

>> Go to 7

>> Repair the (K2) ECT 1 Signal circuit for a short to the

(K900) Sensor Ground 1 circuit.

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

(K2) ECT 1 SIGNAL CIRCUIT OPEN OR HIGH RESISTANCE

Measure the resistance of the (K2) ECT 1 Signal circuit between the
Engine Coolant Temperature Sensor 1 harness connector and the Pow-
ertrain Control Module (PCM) harness connector.

Is the resistance below 5.0 ohms?

Yes

>> Go to 8

>> Repair the (K2) ECT 1 Signal circuit for an open circuit or

high resistance.

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

ENGINE ELECTRICAL DIAGNOSTICS - GPEC

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(K900) SENSOR GROUND 1 CIRCUIT OPEN OR HIGH RESISTANCE

Measure the resistance of the (K900) Sensor Ground 1 circuit between
the Engine Coolant Temperature Sensor 1 harness connector and the
Powertrain Control Module (PCM) harness connector.

Is the resistance below 5.0 ohms?

Yes

>> Go to 9

>> Repair the (K900) Sensor Ground 1 for an open circuit or

high resistance.

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

ENGINE COOLANT TEMPERATURE SENSOR 1

Turn the ignition off.

Connect the Powertrain Control Module (PCM) connector.

Connect a jumper wire between the (K900) Sensor Ground 1 circuit and
the (K2) ECT 1 Signal circuit in the Engine Coolant Temperature Sensor
1 harness connector.

Turn the ignition on.

With the scan tool, read the Engine Coolant Temperature Sensor 1 sig-
nal voltage.

Is the voltage below 1.0 volt with the jumper wire in place?

Yes

>> Replace the Engine Coolant Temperature Sensor 1 in

accordance with the Service Information.

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

>> Go to 10

10.

POWERTRAIN CONTROL MODULE (PCM)

Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Engine Coolant Tem-
perature Sensor 1 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.

Monitor the scan tool data relative to this circuit and wiggle test the wiring and connectors.

Look for the data to change or for the DTC to reset during the wiggle test.

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).

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ENGINE ELECTRICAL DIAGNOSTICS - GPEC

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