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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 in the table below and proceed to the relevant troubleshooting page.

PROBLEM SYMPTOMS

Symptom Suspect Area Test
ABS does not operate Only when 1. to 4. are all normal and the problem is still occurring, replace the ABS & TRAC ECU
3. Check the DTC reconfirming that the normal code is output.
4. IG power source circuit
5. Speed sensor circuit

6. Check the ABS & TRAC actuator with a checker or LEXUS hand-held tester. If abnormal, check the hydraulic circuit for leakage. See CHECK FOR FLUID LEAKAGE .

3. PRE-CHECK 4. IG POWER SOURCE CIRCUIT 5. SPEED SENSOR CIRCUIT 6. ON-VEHICLE INSPECTION
ABS does not operate efficiently Only when 1. to 4. are all normal and the problem is still occurring, replace the ABS & TRAC ECU see,REMOVAL .
1. Check the DTC reconfirming that the normal code is output
2. Speed sensor circuit
3. Stop light switch circuit
4. Check the ABS & TRAC actuator with a checker or LEXUS hand-held tester. If abnormal, check the hydraulic circuit for leakage. See CHECK FOR FLUID LEAKAGE .
1. PRE-CHECK 
2. SPEED SENSOR INSPECTION 
3. STOP LIGHT SWITCH CIRCUIT 
4. ON-VEHICLE INSPECTION
ABS warning light abnormal  
1. ABS warning light circuit
2. ABS & TRAC ECU
1. ABS WARNING LIGHT CIRCUIT 
2. DTC ALWAYS ON ABS & TRAC ECU MALFUNCTION 
BRAKE warning light abnormal 1. BRAKE warning light circuit
2. ABS & TRAC ECU
1. BRAKE WARNING LIGHT CIRCUIT 
2. ABS & TRAC ECU MALFUNCTION 
DTC check cannot be done Only when 1. and 2. are all normal and the problem is still occurring, replace the ABS & TRAC ECU.
1. ABS Warning Light Circuit
2. TRAC OFF Indicator, TRAC Cut Switch Circuit
3. Tc terminal circuit
1. ABS WARNING LIGHT CIRCUIT 
2. TRAC OFF INDICATOR, TRAC CUT SWITCH CIRCUIT 
3. TC TERMINAL CIRCUIT 
Speed sensor signal check cannot be done 1. Ts terminal circuit
2. ABS & TRAC ECU
1. TS TERMINAL CIRCUIT 
2. ABS & TRAC ECU MALFUNCTION 
TRAC does not operate Only when inspection circuits for each problem symptom are all normal and the problem is still occurring, replace the ABS & TRAC ECU.
1. Check the DTC, reconfirming that the normal code is output.
2. IG power source circuit
3. Check the hydraulic circuit for leakage.
4. Speed sensor circuit
1. PRE-CHECK 
2. IG POWER SOURCE CIRCUIT 
3. ON-VEHICLE INSPECTION
4. SPEED SENSOR CIRCUIT 
SLIP indicator light abnormal SLIP Indicator Light Circuit SLIP INDICATOR LIGHT CIRCUIT 
TRAC OFF indicator light abnormal Only when inspection circuits for each problem symptom are all normal and the problem is still occurring, replace the ABS & TRAC ECU.
1. TRAC OFF Indicator, 2. TRAC Cut Switch Circuit
1. TRAC OFF INDICATOR, 2. TRAC CUT SWITCH CIRCUIT