Introduction
How to Perform Trouble DiagnosesBASIC CONCEPT
^ Most important point to perform diagnostic is to understand systems (control and mechanism) in vehicle thoroughly.
^ It is also important to clarify customer complaints before inspection.
First of all, reproduce symptom, and understand it fully.
Ask customer about his/her complaints carefully. In some cases, they will be necessary to check symptom by driving vehicle with customer.
NOTE: Customers are not professionals. Do not assume "maybe customer means..." or "maybe customer mentioned this symptom".
^ It is essential to check symptoms right from beginning in order to repair a malfunction completely.
For an intermittent malfunction, it is important to reproduce symptom based on interview with customer and past examples.
Do not perform inspection on ad hoc basis. Most intermittent malfunctions are caused by poor contacts. In this case, it will be effective to shake suspected harness or connector by hand.
When repairs are performed without any symptom check, no one can judge if malfunction has actually been eliminated.
^ After diagnostic, make sure to perform "ERASE MEMORY". Refer to BRC-26, "ERASE MEMORY". Clearing Trouble Codes
^ For an intermittent malfunction, move harness or harness connector by hand to check poor contact or false open circuit.
^ Always read "General Information" to confirm general precautions.
For Fast and Accurate Diagnosis
PRECAUTIONS FOR DIAGNOSIS
^ Before performing diagnosis, always read General Information to confirm general precautions. Refer to GI-4, "General Precautions". Vehicle Damage Warnings
^ If VDC/TCS/ABS control unit, steering angle sensor, steering system parts, suspension system parts, or tires have been replaced, or if wheel alignment has been adjusted, be sure to adjust neutral position of steering angle sensor before driving.
^ When replacing VDC/TCS/ABS control unit, be sure label on control unit are the same color.
^ After diagnosis is finished, be sure to erase memory.
^ When checking continuity and voltage between unit, be sure to check for disconnection, looseness, bend, or collapse of connector terminals. If any malfunction is found, repair or replace connector terminals.
^ For intermittent symptoms, possible cause is malfunction in harness, harness connector, or terminals. Move harness, harness connector, and terminals to check for poor connections.
^ If a circuit tester is used for the check, be careful not to forcibly extend any connector terminal.
^ To use CONSULT-II to perform self-diagnosis of VDC/TCS/ABS control unit, active tests, or work support, first stop work, then connect CONSULT-II and select "ABS".
^ CONSULT-II self-diagnostic results are displayed without regard to occurrence timing. In some cases later ones (timing value is small) appear on former screen.
^ While self-diagnostic results of CONSULT-II shows malfunction, if CONSULT-II active test is performed, an engine system error may be indicated. In this case, start engine to resume normal screen.
^ VDC/TCS/ABS system electronically controls brake operation and engine output. The following symptoms may be caused by normal operations:
