Dynasty L4-153 2.5L SOHC (1988)
Wheel Speed Sensor: Customer Interest
ABS - Warning Lamp ON, Codes 5 Through 10 Set
NO.: 05-08-90
GROUP:
BRAKES
DATE:
Nov. 5, 1990
SUBJECT:
Wheel Speed Sensor Connector Replacement Bosch ABS Brake System
MODELS:
1988-90 C/AC - DYNASTY/NEW YORKER LANDAU/SALON AY - IMPERIAL/NEW YORKER FIFTH AVENUE
SYMPTOM/CONDITION:
The amber "ANTILOCK" warning lamp is illuminated and a wheel speed sensor fault code (codes 5 through 10) is stored. The fault may be intermittent
and replacement of the wheel speed sensor does not correct the problem.
Some vehicles have been found with the cold solder joints on the vehicle harness side of the wheel speed sensor connector. Since this is a molded
connector, diagnosis may be difficult.
DIAGNOSIS:
Refer to page 5-82 of the 1990 FWD Service Manual, Publication # 81-270-0101, for obtaining fault codes.
Confirm presence of a wheel speed sensor fault to identify the suspect sensor. If a code 9 or 10 is present, test drive the vehicle again, accelerating at a
very slow rate until a code 5 through 8 is obtained.
1.
Upon illumination of the "ANTILOCK" lamp, stop the vehicle, but do not turn off the ignition. Apply the brakes firmly for 10-15 seconds.
2.
Count the number of times the red "BRAKE" warning lamp flashes. This is the fault code.
3.
FAULT CODES: 5 - Left Front Wheel Speed Sensor 6 - Right Front Wheel Speed Sensor 7 - Right Rear Wheel Speed Sensor 8 - Left Rear
Wheel Speed Sensor
Once the suspect sensor is identified, install the MST6100 ABS tester to the 35-way connector in the trunk and plug the cable into the pin-out box. Plug
the leads of an Ohm meter or suitable continuity tester into the terminals for the suspect wheel speed sensor per the following:
Right Front:
Teminals 11 & 21
Left Front:
Teminals 4 & 5
Right Rear:
Teminals 24 & 26
Left Rear:
Teminals 7 & 9
Gain access to the suspected wheel speed sensor connector (the rear sensor connectors are accessed under the car by pulling the grommet from the body;
the front sensor connectors are accessed by removing the sensor grommet retainer in the front wheel well and pulling the grommet from the body).
Gently bend and twist the connector while reading the ohmmeter for continuity. If continuity is lost at any time, the connector should be replaced.
PARTS REQUIRED:
2
Connector pigtail
PN 4414265
2
Heat shrink tube
PN 4419644
REPAIR PROCEDURE:
This procedure involves replacing the existing speed sensor connector.
1.
Disconnect the wheel speed sensor at the connector. For rear speed sensors, gain access to connector and harness by removing the rear seat bottom
cushion. For front sensor connectors, gain access at front wheel wells. Front wheels should be removed.
