Chrysler PT Cruiser, Руководство по обслуживанию и ремонту, Страница: 184 / 2078

These valves are necessary because the pump/motor
supplies more volume than the system requires.
If the brakes are applied at anytime during a trac-
tion control cycle, the brake lamp switch triggers the
control module to switch off traction control.
The traction control function indicator illuminates
during a traction control cycle, displaying TRAC on
the instrument panel.
The traction control system is enabled at each igni-
tion cycle. It may be turned off by depressing the
traction control switch button. The traction control
function indicator (TRAC OFF) illuminates immedi-
ately upon depressing the button. Pressing this but-
ton again or turning off and restarting the vehicle
will enable the traction control system.
If the CAB calculates that the brake temperatures
are high, the traction control system becomes inoper-
ative until a time-out period has elapsed. During this
“thermo-protection mode,” the traction control func-
tion indicator illuminates TRAC OFF; note that no
trouble code is registered.
CAUTION
CAUTIONS
The ABS uses an electronic control module, the
CAB. This module is designed to withstand normal
current draws associated with vehicle operation.
Care must be taken to avoid overloading the CAB
circuits.
CAUTION: In testing for open or short circuits, do
not ground or apply voltage to any of the circuits
unless instructed to do so for a diagnostic proce-
dure.
CAUTION: These circuits should only be tested
using a high impedance multi-meter or the DRBIII
T
scan tool as described in this section. Power
should never be removed or applied to any control
module with the ignition in the ON position. Before
removing or connecting battery cables, fuses, or
connectors, always turn the ignition to the OFF
position.
CAUTION: The CAB 24-way connector should never
be connected or disconnected with the ignition
switch in the ON position.
CAUTION: This vehicle utilizes active wheel speed
sensors. Do not apply voltage to wheel speed sen-
sors at any time.
CAUTION: Use only factory wiring harnesses. Do
not cut or splice wiring to the brake circuits. The
addition of aftermarket electrical equipment (car
phone, radar detector, citizen band radio, trailer
lighting, trailer brakes, etc.) on a vehicle equipped
with antilock brakes may affect the function of the
antilock brake system.
CAUTION: When performing any service procedure
on a vehicle equipped with ABS, do not apply a
12-volt power source to the ground circuit of the
pump motor in the HCU. Doing this will damage the
pump motor and will require replacement of the
entire HCU.
CAUTION: An attempt to remove or disconnect cer-
tain system components may result in improper
system operation. Only those components with
approved removal and installation procedures in
this manual should be serviced.
CAUTION: If welding work is to be performed on the
vehicle, using an electric arc welder, the CAB con-
nector should be disconnected during the welding
operation.
CAUTION: Many components of the ABS System
are not serviceable and must be replaced as an
assembly. Do not disassemble any component
which is not designed to be serviced.
CAUTION: Only the recommended jacking or hoist-
ing positions for this vehicle are to be used when-
ever it is necessary to lift a vehicle. Failure to raise
a vehicle from the recommended locations could
result in lifting a vehicle by the hydraulic control
unit mounting bracket. Lifting a vehicle by the
hydraulic control unit mounting bracket will result
in damage to the mounting bracket and the hydrau-
lic control unit.
CAUTION: Brake fluid will damage painted surfaces.
If brake fluid is spilled on any painted surface,
wash off with water immediately.
DIAGNOSIS AND TESTING - INSPECTION AND
ROAD TEST
(1) Visually inspect the ABS for damaged or dis-
connected components and connectors.
(2) Verify the brake lamps are operational. If they
are not, repair them prior to continuing.
5 - 76 BRAKES - ABS
PT
BRAKES - ABS (Continued)