Dodge ZB 2005 Service Manual page 1260

Symptom:
P1281-ENGINE IS COLD TOO LONG
When Monitored and Set Condition:
P1281-ENGINE IS COLD TOO LONG
When Monitored: The ignition key on, engine running.
Set Condition: The engine does not warm to 176 deg. F while driving for 20 minutes after
start.
ENGINE COLD TOO LONG
ECT SENSOR OPERATION
TEST
1 Note: The best way to diagnose this DTC is to allow the vehicle to remain
outside overnight in order to have a completely cold soaked engine.
Note: Extremely cold outside ambient temperatures may cause this DTC to
set.
Verify that the coolant level is not low and correct as necessary.
Start the engine.
With the DRBIII , set the engine RPM to 1500 and allow the engine to warm up for
10-15 minutes.
With the DRBIII , monitor the ENG COOLANT TMP DEG value during the warm
up cycle. Make sure the transition of temperature change is smooth.
Did the engine temperature reach a minimum of 80° C (176° F)?
Yes → Go To 2
→ Refer to the Service Information for cooling system performance
No
2 WARNING: MAKE SURE THE ENGINE COOLING SYSTEM IS COOL BE-
FORE REMOVING THE PRESSURE CAP OR ANY HOSE. SEVERE PER-
SONAL INJURY MAY RESULT FROM ESCAPING HOT COOLANT. THE
COOLING SYSTEM IS PRESSURIZED WHEN HOT.
With the DRBIII , read and record the ECT Sensor Temperature value.
Using the DRB Temperature Probe #CH7050, measure the engine coolant tempera-
ture.
NOTE: The t-stat housing area should be around 192-195 at start to open.
Is the ECT Sensor value with -15°C (5°F) of the temperature probe reading?
Yes → Test Complete.
→ Replace the ECT Sensor.
No
POSSIBLE CAUSES
ACTION
diagnosis. The most probable cause is a Thermostat problem.
Also, refer to any related TSBs.
Perform POWERTRAIN VERIFICATION TEST VER - 2.
Perform POWERTRAIN VERIFICATION TEST VER - 2.
DRIVEABILITY - GAS
139
APPLICABILITY
All
All