Technical Service Bulletins
|Publication Date: February 22, 2005|
|1999-2001 Explorer, Windstar|
2000-2001 Excursion, Expedition
2001 F-Super Duty
This article supersedes TSB 04-26-2 to update the vehicle lines and model years.
Vehicles equipped with the parking aid reverse sensing system (RSS) may sound a warning tone when the vehicle is in reverse, even though there are no objects behind the vehicle. This condition may also occur on vehicles equipped with the forward sensing system (FSS) when vehicle is in reverse or drive.
The condition MAY NOT be due to proximity sensor(s) malfunction but may be a normal operation characteristic, or due to sensor contamination (sensor being covered with dirt). Refer to the following description of OPERATION AND COMMON CAUSE OF WARNINGS, before replacing any sensor(s).
|NOTE:||THE FOLLOWING DESCRIPTIONS ARE TRUE FOR BOTH THE RSS AND FSS.|
OPERATION AND COMMON CAUSE OF WARNINGS
The RSS is only operational when the vehicle is in reverse. For vehicles also equipped with the FSS the system is operational when the vehicle is in reverse or drive.
The FSS and RSS give an audible warning to the driver when obstacles are within 6′ (1.8 meters) from the vehicle, and when obstacles are within 18″ (46 cm) on either side of the bumper.
|NOTE:||CERTAIN OBSTACLES MAY BE DIFFICULT FOR THE RSS/FSS TO DETECT DEPENDING ON GEOMETRIC SHAPE OR PROFILE OF THE OBJECT AND THE MATERIAL THE OBJECT IS COMPOSED OF.|
|NOTE:||THE NEAREST OBSTACLE WILL ALWAYS BE THE OBSTACLE REPORTED, WITH THE EXCEPTION STATED IN THE NOTE ABOVE.|
|NOTE:||THE VEHICLE OPERATOR MUST BE AWARE THAT THE WARNING TONES ARE AT A MODERATE VOLUME LEVEL AND THAT THE TONES MAY BE DIFFICULT TO HEAR WITH BACKGROUND NOISE (RADIO, BLOWERS, PASSENGER CONVERSATION, ETC). THE RSS/FSS SPEAKER VOLUME IS ALREADY AT MAXIMUM VOLUME AND IS NOT ADJUSTABLE.|
In cases where the RSS/FSS give warnings but nothing is within range of the vehicle sensors, or give warnings for 3 seconds then ceases, the occurrence may be due to any of the following reasons:
BLOCKED/CONTAMINATED PROXIMITY SENSOR SURFACE:
Proximity sensor surfaces may be covered with snow, ice, dirt or mud. There is a gap between the sensor membrane and its plastic housing that must remain clear (Figure 1). If this space is contaminated with any foreign material the system may sound a continuous tone or intermittent tone. The sensor surface can be cleaned by a high pressure water spray.
Figure 1 – Article 05-4-18
SIDE COVERAGE SENSOR:
There is side/rear coverage that extends approximately 18″ (46 cm) perpendicular from the side rear fascia. Side coverage is a desirable feature in a parking situation where the vehicle is involved in a very tight turn with little rearward movement, or where the vehicle is backing parallel to a large, extending obstacle such as a garage wall. If there is no encroachment between any of the outer sensors and an obstacle, then the warning will sound for 3 seconds and cease. If vehicle or the obstacle begin to move closer to each other, then the warning will begin again. Obstacles within 10″ (25 cm) of the fascia will always be reported with a continuous tone. This is considered normal operation.
ABNORMAL ROAD SURFACES:
The RSS/FSS may give warnings due to certain road surfaces with surface projections such as rocks, broken pavement, unplowed snow covered roads. This is considered normal operation.
OTHER POSSIBLE CAUSES:
Very wet weather conditions, such as mist, frost or snow may provoke occasional warnings. The system may detect liftgate while open and certain trailer hitches and/or bicycle racks. External ultrasonic noise may be detected (high velocity air, machinery). This is considered normal operation.
- Ensure that nothing is in detectable sensor-range 6′ (1.8 meters) behind vehicle for the RSS and within 6′ (1.8 meters) of the front of the vehicle for the FSS.
- Clean proximity sensors with a dry shop towel, and if required wash with water or a high pressure water wash to ensure that the membrane gap is free of any dirt or contamination.
- Using the New Generation Star (NGS) tester or WDS, observe the following four (4) parking aid module parameter identification displays (PIDs) for distance information:
- LR_CNTD (NGS)/LRI_DIST (WDS): (Left Rear Center Sensor Distance To Obstacle)
- RR_CNTD (NGS)/RRI_DIST (WDS): (Right Rear Center Sensor Distance To Obstacle)
- LR_CNRD (NGS)/LRO_DIST (WDS): (Left Rear Corner Sensor Distance To Obstacle)
- RR_CNRD (NGS)/RRO_DIST (WDS): (Right Rear Corner Sensor Distance To Obstacle)
NOTE: PID IDENTIFIERS ALSO EXIST FOR FRONT SENSORS IF EQUIPPED.
- If the sensor is functioning properly, with no objects in range of the vehicle, each sensor PID as described above should display a full scale numerical reading of 255 cm (NGS) or 100 inches (NGS+ and WDS).
- If a PID reading other than 255 or 100 displays, replace only the sensor that is out of specification. Refer to Workshop Manual Section 413-00 as needed for removal and installation procedures.
ACCESSING PIDS WITH NGS, SELECT:
- Vehicle Line
- Diagnostic Data Link
- PID/Data Monitor And Record
- Select the appropriate PIDS
ACCESSING PIDS WITH WDS, START VEHICLE SESSION THEN SELECT:
- Toolbox Icon
- Datalogger, Then Tick (Check Mark)
- Modules, Then Tick
- PAM, Then Tick
- Select The Appropriate PIDS, Then Tick
Eligible Under Provisions Of New Vehicle Limited Warranty Coverage
|BASIC PART NO.||CONDITION CODE|