Chrysler Front Wheel Drive Cars 6-CYL 1988-1995 Repair Information

General Information



See Figures 1 and 2

The New Yorker, Imperial, Dynasty, Fifth Ave., Premier and Monaco models came equipped with one of two systems, depending on the model year of the vehicle: 1988-90 vehicles were equipped with Bosch III ABS, and 1991-95 vehicles were equipped with Bendix Type 10 ABS.

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Fig. Fig. 1: Four wheel Anti-lock Brake System (ABS) component locations-Premier and Monaco

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Fig. Fig. 2: Four wheel Anti-lock Brake System (ABS) component locations-New Yorker, Dynasty, Imperial and Fifth Ave. models


See Figures 3 and 4

The purpose of the Anti-lock Brake System (ABS) is to prevent wheel lock-up under heavy braking conditions on virtually any type of road surface. ABS is desirable because a vehicle which is topped without locking the wheels will retain directional stability and some steering capability. This allows the driver to retain greater control of the vehicle during heavy braking.

Under normal braking conditions, the ABS functions the same as a standard brake system with a diagonally split master cylinder and conventional vacuum assist.

If wheel locking tendency is detected during application, the system will enter anti-lock mode. During anti-lock mode, hydraulic pressure in the four wheel circuits is modulated to prevent any wheel from locking. Each wheel circuit is designed with a set of electrical valves and hydraulic line to provide modulation, although for vehicle stability, both rear wheel valves receive the same electrical signal. The system can build or reduce pressure at each wheel, depending on signals generated by the Wheel Speed Sensors (WSS) at each wheel and received at the Controller Anti-lock Brake (CAB).

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Fig. Fig. 3: If the pump/motor does not function correctly, have the relay checked before purchasing a new pump/motor assembly

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Fig. Fig. 4: The ABS relay and yellow lamp relay are the other 2 relays in the ABS system


Failure to observe the following precautions may result in system damage:

Before performing electric arc welding on the vehicle, disconnect the control module and the hydraulic unit connectors.
When performing painting work on the vehicle, do not expose the control module to temperatures in excess of 185°F (85°C) for longer than 2 hours. The system may be exposed to temperatures up to 200°F (95°C) for less than 15 minutes.
Never disconnect or connect the control module or hydraulic modulator connectors with the ignition switch ON .
Never disassemble any component of the Anti-Lock Brake System (ABS) which is designated unservicable; the component must be replaced as an assembly.
When filling the master cylinder, always use brake fluid which meets DOT-3 specifications; petroleum-based fluid will destroy the rubber parts.
Working on ABS system requires extreme amount of mechanical ability, training and special tools. If you are not familiar have your vehicle repaired by a certified mechanic or refer to a more advanced publication on this subject.


See Figure 5

For the proper diagnostic procedure for either the entire ABS system or a single component of the system, a scan tool (DRB, DRB II or equivalent) is necessary. Because of the complexity of the ABS system and the importance of correct system functioning, it is a good idea to have a qualified automotive mechanic test the system if any problems have been detected.

The self-diagnostic ABS start up cycle begins when the ignition switch is turned to the ON position. An electrical check is completed on the ABS components, such as the wheel speed sensor continuity and other relay continuity. During this check the amber anti-lock light is turned on for approximately 1-2 seconds.

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Fig. Fig. 5: The ABS diagnostics connector is a light blue 6-way connector, located under the dash and on the left side of the steering column

Further functional testing is accomplished once the vehicle is set in motion.

The solenoid valves and the pump/motor are activated briefly to verify function
The voltage output from the wheel speed sensors is verified to be within the correct operating range

If the vehicle is not set in motion within 3 minutes from the time the ignition switch is set in the ON position, the solenoid test is bypassed, but the pump/motor is activated briefly to verify that it is operating correctly.

Fault codes are kept in a non-volatile memory until either erased by the DRB II or erased automatically after 50 ignition cycles (key ON-OFF cycles). The only fault that will not be erased after the 50 ignition cycles is the CAB fault. A CAB fault can only be erased by the DRB II. More than one fault can be stored at a time. The number of key cycles since the most recent fault was stored is also displayed. Most functions of the CAB and ABS system can be accessed by the DRB II for testing and diagnostic purposes.