FixVault

Problem Symptoms Table

If a normal code is displayed during the DTC check but the problem still occurs, check the circuits for each problem symptom in the order given and proceed to the relevant troubleshooting procedure. See ABS & HYDRAULIC BRAKE BOOSTER POWER SUPPLY SYSTEM PROBLEM SYMPTOMS  table.

NOTE: When replacing ABS & BA & TRAC & VSC ECU, sensor or etc., turn the ignition switch OFF.
ABS & HYDRAULIC BRAKE BOOSTER POWER SUPPLY SYSTEM PROBLEM SYMPTOMS

Symptom Suspect Area Refer To
ABS does not operate Only when 1. to 4. are all normal and the problem is still occurring, replace the ABS & BA & TRAC & VSC ECU.
  1. Reconfirm the DTC and check that the normal code is output.
  2. IG power source circuit
  3. Speed sensor circuit
  4. Check the hydraulic brake booster with a checker or LEXUS hand-held tester.

If abnormal, check the hydraulic circuit for leakage (See CHECK FOR FLUID LEAKAGE in VEHICLE SKID CONTROL & BRAKE ASSIST SYSTEM - DIAGNOSIS - GS 300 & GS 430 article).
PRE-CHECK 
DTC C1241/41: IG POWER SOURCE CIRCUIT 
DTC C0200/31-C0215/34: SPEED SENSOR CIRCUIT 
HYDRAULIC BRAKE BOOSTER article
ABS does not operate efficiently Only when 1. to 4. are all normal and the problem is still occurring, replace the ABS & BA & TRAC & VSC ECU.
  1. Reconfirm the DTC and check that the normal code is output.
  2. Speed sensor circuit
  3. Stop light switch circuit
  4. Check the hydraulic brake booster with a checker or LEXUS hand-held tester.

If abnormal, check the hydraulic circuit for leakage (See CHECK FOR FLUID LEAKAGE in VEHICLE SKID CONTROL & BRAKE ASSIST SYSTEM - DIAGNOSIS - GS 300 & GS 430 article).
PRE-CHECK 
DTC C0200/31-C0215/34: SPEED SENSOR CIRCUIT 
DTC C1249/49: STOP LIGHT SWITCH CIRCUIT 
HYDRAULIC BRAKE BOOSTER article
ABS warning light abnormal
  1. ABS warning light circuit
  2. ABS & BA & TRAC & VSC ECU
ABS WARNING LIGHT CIRCUIT 
 
DTC check cannot be done Only when 1. and 2. are all normal and the problem is still occurring, replace the ABS & BA & TRAC & VSC ECU.
  1. ABS warning light circuit
  2. Tc terminal circuit
ABS WARNING LIGHT CIRCUIT 
TC TERMINAL CIRCUIT 
Speed sensor signal check cannot be done
  1. Ts terminal circuit
  2. ABS & BA & TRAC & VSC ECU
TS TERMINAL CIRCUIT