ABS - False Activation/DTCs Stored/Grinding/Whining
Article No.98-14-8
07/20/98
^ BRAKES - ANTI-LOCK - ABS FALSE ACTIVATION
AND/OR INTERMITTENT ABS LAMP ON WITH
DIAGNOSTIC TROUBLE CODES (DTCS) 1145, 1155,
1230, 1233, 1234, AND/OR 1237 STORED IN
MEMORY
^ BRAKES - PULLS WHEN ABS PUMP RUNS
^ NOISE - "GRINDING" AND/OR "WHINING"-
ANTI-LOCK BRAKES - ABS FALSE ACTIVATION
AND/OR INTERMITTENT ABS LAMP ON WITH
DIAGNOSTIC TROUBLE CODES (DTCS) 1145, 1155,
1230, 1233, 1234, AND/OR 1237 STORED IN
MEMORY
LIGHT TRUCK:
1995-97 EXPLORER
1997 MOUNTAINEER
This TSB article is being republished in its entirety to correct the warranty condition code.
ISSUE
The Anti-lock Brake System (ABS) may activate under false ABS conditions. The customer may notice a "grinding," "whining," "pulsing," or "fluttering" at the brake pedal at speeds below 19 km/h (12 mph). The ABS lamp may also illuminate and Diagnostic Trouble Codes (DTCs) 1145, 1155, 1230, 1233, 1234, and/or 1237 may be stored in memory. This may be caused by corrosion at the ABS sensor connectors, a damaged sensor wire due to a faulty crimp, or damage to the ABS sensor indicator.
ACTION
Diagnose and repair the vehicle by referring to the following Anti-lock False Activation Diagnosis And Service Procedure for details.
NOTE
ABS FALSE ACTIVATION CONCERNS CAN OCCUR ON THESE VEHICLES REGARDLESS OF WHETHER THE ABS LAMP IS ILLUMINATED OR NOT, OR IF DTCs ARE SET OR NOT.
ANTI-LOCK FALSE ACTIVATION DIAGNOSIS AND SERVICE PROCEDURE
Refer to Figure 1 for the following procedure.
1. Determine if the ABS system is working to design intent by test driving. Refer to the following during drive:
^ Turn off all accessories so that the ABS pump motor can be heard.
^ Drive vehicle at a speed of 32 km/h (20 mph).
^ Perform a light to medium normal traffic stop and feel for a pulsation in the brake pedal. False activation is likely to initiate at speeds below 19 km/h (12 mph).
^ If the vehicle pulls when the pump motor begins to run, the front sensor opposite the direction of the pull is suspect. Pressing harder on the pedal once the pump motor turns on should cause the steering wheel to veer further in the direction of the pull.
^ If pulsation is present without a significant pull, the rear sensor is suspect.
^ To confirm the vehicle pull is a result of the ABS, disable the ABS by removing the fuse (14) and re-evaluate. If the pull is still present, use the Vehicle Pulls While Braking symptom (refer to the appropriate Explorer/Mountaineer Workshop Manual, Section 204-00) to diagnose and correct the problem before restarting this procedure.
2. Use New Generation Star (NGS) Tester to determine if ABS diagnostic codes are present. For each code found, follow the Workshop Manual Pinpoint Test and recommended repair procedure. If the Pinpoint Test leads to sensor replacement, read entire article for important service tips. Verify the repair by repeating Step 1. If no codes are present or Pinpoint Test(s) lead to "NO PROBLEM FOUND," then continue then Step 3.
3. Inspect the system components for any obvious signs of damage. Closely inspect the wiring for signs of wear and potential shorts. If sensor is damaged, read entire article for important service tips. Repair or replace damaged components and verify the repair by repeating Step 1.
4. For the sensor identified in Step 1, remove sensor and inspect the sensor indicator (tone ring) for any damage or missing teeth. Rotate wheel or axle to ensure all teeth are checked.
5. If sensor indicator is damaged, replace and proceed to next Step.
CAUTION
PLUGGING THE SENSOR HOLE IS CRITICAL. DAMAGE TO THE WHEEL BEARING INSIDE WILL OCCUR IF DEBRIS FROM THE CLEANING OPERATION SHOULD HAPPEN TO FALL IN THE HOLE.
6. Plug the hub assembly opening for the sensor to keep it free of debris. Thoroughly clean the hub mating surface using fine grade sand paper or a wire brush to make certain it is completely free of all corrosion.
7. For front sensors, apply a conservative layer of High Temperature 4X4 Wheel Bearing And Axle Grease (E8TZ-19590-A, or equivalent meeting Ford specification ESA-MIC198-A) between the ABS sensor body and the machined pad on the bearing forging to prevent future corrosion. Be careful to keep the sensor opening and the sensor indicator free of grease.
8. If sensor indicator was replaced in Step 5, reinstall sensor and verify the repair by repeating Step 1.
9. If sensor indicator was not damaged or replacing indicator failed to correct the problem, replace sensor with recommended service part reference in the Parts Block at the end of this article, and verify repair by repeating Step 1.
NOTE
THE 1998 4X4 FRONT SENSOR HAS A STRONGER SIGNAL THAN PREVIOUS RELEASE. FOR PROPER OPERATION, THE SENSORS MUST HAVE MATCHING LEVELS. REPLACE OPPOSITE FRONT WHEEL SENSOR ON 1995-97 4X4 MODELS ASSUMING IT IS THE PRIOR LEVEL.
10. If problem still exists, one of the following is most likely:
^ the sensor indicator is damaged or defective
^ installation of the new sensor was not properly performed
^ another sensor signal is weak
11. Verify the installation making certain the indicator and sensor head are free of grease. If installation is correct, replace the hub assembly and install new indicator in the side identified in Step 1. Verify the repair by repeating Step 1.
12. If problem still exists, replace other sensors following the recommendations outlined in this article.
OTHER APPLICABLE ARTICLES: 96-16-3
SUPERSEDES: 98-8-9
WARRANTY STATUS: Eligible Under The Provisions Of Bumper To Bumper Warranty Coverage
OPERATION DESCRIPTION TIME
981408A Diagnose Anti-lock Brake 0.8 Hr.
System
981408BT Replace Front Sensor 1.0 Hr.
Indicator - Both Sides
(4X2)
981408B Replace Front Sensor 0.6 Hr.
Indicator - One Side (4X2)
981408CT Replace Front Sensor 1.4 Hrs.
Indicator - Both Sides
(4X4)
981408C Replace Front Sensor 0.8 Hr.
Indicator - One Side (4X4)
981408DT Replace Front Sensor - 0.5 Hr.
Both Sides (4X2)
981408D Replace Front Sensor - 0.3 Hr.
One Side (4X2)
981408ET Replace Front Sensor - 0.9 Hr.
Both Sides (4X4)
981408E Replace Front Sensor - 0.6 Hr.
One Side (4X4)
981408F Replace Rear Sensor 1.7 Hrs.
Indicator
981408G Replace Rear Sensor 0.3 Hr.
981408H Replace Rear Sensor And 1.8 Hrs.
Rear Sensor Indicator
981408I Replace Sensor Connector 0.5 Hr.
Terminal Ends And/Or
Replace Eight (8) Terminal
Ends At 28-Way Connector
DEALER CODING
CONDITION
BASIC PART NO. CODE
2C204 42
OASIS CODES: 206000, 301000, 702000, 702100