How To Perform Trouble Diagnoses For Quick And Accurate Repair: Introduction

The TCS has two electronic control units. One is called the TCS/ ABS control unit. The ABS system has an electronic control unit to control major functions and for the ABS. The other is the throttle control module (TAC module) which is used to control the throttle opening. The control units accept input signals from sensors and instantly drive actuators. It is essential that both kinds of signals are proper and stable. Also there should be no such conventional problems as oil leaks in the TCS operating circuits. Nor should there be lack of brake fluid or other problems with the brake system.

It is much more difficult to diagnose a problem that occurs intermittently rather than continuously. Most intermittent problems 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 problems, so a road test should be carried out.

Before undertaking actual checks, take just a few minutes to talk with a customer who approaches with a TCS complaint. The customer is a very good source of information on such problems; 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" problems first. This is one of the best ways to troubleshoot brake problems on a TCS controlled vehicle. Also check related Service Bulletins for information.

It is strongly recommended that the TCS/ABS control unit be checked for electrical problems first. Then check the TAC module.