Tech Tip: Ford Traction Control Light On/No DTC, or DTC P1889 – UnderhoodService

Tech Tip: Ford Traction Control Light On/No DTC, or DTC P1889

Some 2005-’07 Five Hundred, Freestyle and Montego vehicles equipped with all wheel drive (AWD) may exhibit the traction control warning lamp on.

Affected vehicles: 2005-’07 Ford Five Hundred, Freestyle; 2005-’07 Montego

Issuing a Self Test
Some 2005-’07 Five Hundred, Freestyle and Montego vehicles equipped with all wheel drive (AWD) may exhibit the traction control warning lamp on. If the traction control lamp is on but no DTCs are retrieved, be sure to directly self test the DEM (4X4 module) using the diagnostic scan tool.

Service Procedure
1. Install a diagnostic scan tool and retrieve any available DTCs from the DEM, ABS module and instrument cluster. If there are DTCs in the ABS module or instrument cluster, do not continue with this TSB.

Note: Although the same warning lamp is shared for both systems, the DTCs for the AWD and traction control system are not stored in the Powertrain Control Module (PCM) as on some other Ford/ Mercury vehicles. The DEM (4×4 module) must be selected, as it is an optional module only used on AWD vehicles. Traction control DTCs are stored in the ABS module. Vehicle wiring and communication DTCs related to the AWD and traction control system are stored in the instrument cluster.

2. If DTC codes other than P1889 are present in the DEM, follow additional diagnostic routines and do not follow this TSB procedure.

3. If DTC code P1889 is the only code present in the DEM, replace the oil pressure/temperature sensor (4B487) and clear the code.

Note: When replacing the oil pressure/temperature sensor, the O-ring seal on the adjacent solenoid valve must also be replaced.

Note: The solenoid valve normally comes out of the on-demand coupling as the DEM is removed. If it does not, either remove it by hand, or carefully remove it with pliers.

4. Remove the existing O-ring from the coupling body.

5. Install the new O-ring included in the Pressure Sensor Kit, on the solenoid valve.

6. Install the solenoid valve and oil pressure/emperature sensor into the DEM (not into the ­coupling body) prior to assembling the DEM to the coupling body.

Note: Install the oil pressure/temperature sensor washer with the concave (dished) side facing the DEM.

7. Perform a test drive.

a. Start the engine and allow the vehicle to idle for a minimum of 5 minutes with the transmission in park.

b. Perform five 0-25 MPH (0-40 Km/h) wide-open-throttle accelerations.

Courtesy of Ford Motor Co., TSB 08-4-11

You May Also Like

Belts and Pulley Alignment

A misalignment of the plane of the belt can occur when a pulley is not parallel to the other pulleys on the belt drive system.

Drive Belt Alignment Alignment is key to the health of an engine belt. The belt drive system is designed to create friction between the grooves on the belt and pulley to transfer power from the crankshaft to the alternator, water pump or power steering pump. If the grooves on the belt do not align with the pulleys, the friction won’t be evenly applied and can result in wear and noise.

ECM Damage

Engineers have devised two strategies that can be called the “immune system” for the electrical system.

Voltage Drop Testing

The measurement of voltage is like the speed of the traffic.

Spark Plug Fouling

Understanding why spark plugs get dirty.

Understanding Stop/Start Charging and Starting Systems

The problem may not have been caused by a complicated reason, something simple may have caused the system not to work.

Other Posts

Hybrid Vehicle Fluid Maintenance

There are opportunities your shop can’t pass up just because the car or SUV has a hybrid badge on the back.

Ignition Coil Output

To see inductance inside the primary windings, use an amp probe placed around the positive wire for the ignition coil.

Caring For AGM And Flooded Car Batteries

Faulty battery cables, if loose, corroded, or damaged, can lead to power drainage.

Power Window Regulator and Motor Service

Power windows are great as long as they roll up and down when commanded to do so.