Mazda MX-6 1998, Workshop Manual

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TROUBLESHOOTING
PRECA U TIO N
When inspecting or servicing the ABS/TCS, note the
following points:
1. The ABS warning light, the TCS indicator light and
the TCS OFF light stay on until the ignition switch
is turned to OFF under the following condition.
When the rear wheel is locked by the jack up,
stack or chassis roller, and only the front wheel is
spinning for more than
60 seconds.
2. The ABS warning light may flash when driving
under the following conditions. In this case, the
ABS is operating normally. Investigate and
determine if the warning light illuminates before
operation.
(1) Parking brake is not fully released while
driving.
(2) Continuous application of the brake.
(3) Sudden acceleration or deceleration.
(4) Left/right or front/rear tires are in different
conditions. Tire sizes other than those listed
on the tire label, or tires with different radii,
pressures or wear are used.
3. The TCS indicator light and the TSC OFF light
illuminate under the following conditions. In this
case, the TCS is operating normally. Investigate
and determine if the lights illuminate before
operation.
(1) Using TCS OFF switch to cancel the TCS
operation. Press the TCS OFF switch and the
system is in standby mode.
(2) The water temperature is below 0 °C (32 °F}.
In this case, the TCS OFF light stays lit until
the engine is warm, (maximum 15 min.)
(3) Battery is low. In this case, the TCS OFF light
and ABS warning light stay lit until battery
voltage is increased.
4. When performing a repair, if the ABS/TCS related
connectors are disconnected and the ignition
switch is turned to ON, the control module will
detect a fault and record it as a malfunction.
5. After repairing the ABS wheei-speed sensor or
pump motor, the ABS warning light may not go off
when the ignition switch is turned to ON. In this
case, drive the vehicle at a speed of more than 10
km /h {6.2 mph}.
After the ABS warning light goes
off, reset the memory.
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6. The ABS and TCS are composed of electrical and
mechanical parts. It is necessary to treat them
separately as electrical system and hydraulic
system when performing troubleshooting.
(1) Malfunctions in electrical system
© The ABS/TCS control module (ABS/TCS
CM) has an on-board diagnostic function.
With this function, the ABS warning light
illuminates when there is a problem in the
electrical system. Also, past and present
malfunctions are recorded in the ABS/TCS
CM. This function can find malfunctions
that do not occur during periodic
inspection. To find malfunctions with the
ABS/TCS, perform the on-board
diagnostic inspection. Erase the diagnostic
trouble code in the A B S TC S CM memory
after repair. Also, if A B S TC S related parts
have been replaced, verify that the
diagnostic trouble code has been erased
afterwards.
(D
The AB S TC S CM is composed of delicate
electronic parts. If foreign materials get
inside the CM, the CM will malfunction and
ABSTC S cannot operate. When replacing
the CM, make sure there are no foreign
materials in the CM’s system connector.
(2) Malfunctions in hydraulic system
0 Hydraulic system malfunction is similar to
a malfunction in normal brake system. It
must be determined if a malfunction is in
the ABS components or in normal brake
system. This guide omits information for
normal brake components and only
contains information for ABS components
(the ABS hydraulic unit).
(D
The ABS hydraulic unit contains delicate
mechanical parts. If foreign materials get
in, malfunction could occur, and the ABS
will fail to operate. Also, if the normal
brake operates but the ABS does not, the
cause of the problem is very difficult to
determine. Therefore, when servicing the
ABS, such as changing brake fluid or
detaching pipes, be careful that no foreign
materials get inside.
A N TILO C K BRAKE SYSTEM AND TR AC TIO N C O N TRO L SYSTEM O N-BO ARD DIAG NOSIS
O n-B oard D iagnostic (OBD) Test Description
• The OBD test checks the integrity and function of
the A B S T C S and outputs the test results when
requested by the NGS tester. If also provides a
quick end check of the ABSTC S, is usually
performed at the start of each diagnostic
procedure with all accessories off and is
performed at end of most troubleshooting tests for
verification of repair and make sure no other faults
were incurred while servicing a previous fault.
• The OBD test is divided into three test: Read/clear
diagnostic results, PID monitor and record and
active command modes.
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R ead/clear diagnostic results
• This function allows to read or clear DTCs in the
A B S TC S control module memory.
PID m onitor and record
• This function allows to access certain data values,
input signals, calculated values, and system
status information.
A ctive com m and modes
• This function allows to control devices through the
NGS.
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