SEF233G
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How to Perform Trouble Diagnoses for Quick
and Accurate Repair
NHBR0153
INTRODUCTION
NHBR0153S01
The ABS/TCS system has an electronic control unit to control major
functions. The control unit accepts input signals from sensors and
instantly drives actuator. It is essential that both kinds of signals are
proper and stable. It is also important to check for conventional
incidents: such as air leaks in the booster or lines, lack of brake
fluid, or other incidents with the brake system.
It is much more difficult to diagnose an incident that occurs inter-
mittently rather than continuously. Most intermittent incidents are
caused by poor electric connections or faulty wiring. In this case,
careful checking of suspicious circuits may help prevent the
replacement of good parts.
A visual check only may not find the cause of the incidents, so a
road test should be performed.
Before undertaking actual checks, take just a few minutes to talk
with a customer who approaches with an ABS/TCS complaint. The
customer is a very good source of information on such incidents;
especially intermittent ones. Through the talks with the customer,
find out what symptoms are present and under what conditions
they occur.
Start your diagnosis by looking for “conventional” incidents first.
This is one of the best ways to troubleshoot brake incidents on an
ABS/TCS controlled vehicle. Also check related Service Bulletins
for information.
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TROUBLE DIAGNOSIS — INTRODUCTION
TCS
How to Perform Trouble Diagnoses for Quick and Accurate Repair
BR-53