Page 1684 of 4592
DI±472
± DIAGNOSTICSAUTOMATIC TRANSAXLE (A541E)
707 Author: Date:
DTC P1520 Stop Light Switch Signal Malfunction
CIRCUIT DESCRIPTION
The purpose of this circuit is to prevent the engine from stalling, while driving in lock±up condition, when
brakes are suddenly applied.
When the brake pedal is operated, this switch sends a signals to ECM. Then the ECM cancels operation
of the lock±up clutch while braking is in progress.
DTC No.DTC Detecting ConditionTrouble Area
P1520No stop light switch signal to ECM during driving.
(2 trip detection logic)Open or short in stop light switch circuit
Stop light switch
ECM
WIRING DIAGRAM
See page DI±363.
INSPECTION PROCEDURE
See page DI±363.
DI02O±02
Page 1703 of 4592
DI03A±02
Vehicle Brought to Workshop
Customer Problem Analysis
P. DI±492
Check and Clear DTC (Precheck)
P.
DI±493
Items inside
are titles of pages in this manual,
with the page number in the bottom portion. See
the pages for detailed explanations.
Problem Symptom ConfirmationSymptom Simulation
P. IN±21
Symptom
does not occur
Symptom
occurs
DTC Check
P. DI±493
Sensor CheckCircuit Inspection
P. DI±502 ~ DI±534
DTC Chart
P. DI±497 Malfunction codeProblem Symptoms Table
P. DI±501
Check for Fluid Leakage
P. DI±536
Identification of Problem
Normal code
Repair
Confirmation Test
End
1
2
3
4
5
67
89
10
11
Step 2, 5, 8, 9, 11:Diagnostic steps permitting the use of the
TOYOTA hand±held tester or TOYOTA
break±out±box.
± DIAGNOSTICSANTI±LOCK BRAKE SYSTEM (DENSO Made)
DI±491
726 Author: Date:
ANTI±LOCK BRAKE SYSTEM (DENSO Made)
HOW TO PROCEED WITH TROUBLESHOOTING
Troubleshoot in accordance with the procedure on the following pages.
Page 1704 of 4592
DI03B±02
ABS Check Sheet
Inspector 's
Name:
Customer 's Name
Date Vehicle
Brought InRegistration Year Registration No.
Frame No.
Odometer Reading/ /
/ /
Date Problem First Occurred
Frequency Problem Occurs/ /
ContinuousIntermittent ( times a day)
Remains ONDoes not Light Up
DTC Check1st Time
2nd TimeNormal Code
Malfunction Code (Code )
Normal CodeMalfunction Code (Code )
Symptomskm
miles
ABS does not operate.
ABS Warning Light
AbnormalABS does not operate efficiently. DI±492
± DIAGNOSTICSANTI±LOCK BRAKE SYSTEM (DENSO Made)
727 Author: Date:
CUSTOMER PROBLEM ANALYSIS CHECK
Page 1705 of 4592
DI03C±03
F00047
F00006
DLC1Short Pin
S-17-1 Iei-23-1-A
F00041
DLC2 DLC1
Tc E1
E1Tc
R01346
Normal Code
0.25 sec.
0.25 sec. 2 sec.
ON
OFF
ON
OFF0.5 sec. 0.5 sec.
Code 11 and 21
4 sec.1.5 sec.
2.5 sec.
Code 11 Code 21
± DIAGNOSTICSANTI±LOCK BRAKE SYSTEM (DENSO Made)
DI±493
728 Author: Date:
PRE±CHECK
1. DIAGNOSIS SYSTEM
(a) Check the indicator.
When the ignition switch is turned ON, check that the ABS
warning light goes on for 3 seconds.
HINT:
If the indicator check result is not normal, proceed to
troubleshooting for the ABS warning light circuit
(See page DI±529).
(b) Check the DTC.
(1) Disconnect the short pin from DLC1.
(2) Using SST, connect terminals Tc and E
1 of DLC2 or
DLC1.
SST 09843 ± 18020
(3) Turn the ignition switch ON.
(4) Read the DTC from the ABS warning light on the
combination meter.
HINT:
If no code appears, inspect the diagnostic circuit or ABS
warning light circuit (See page DI±532 or DI±529).
As an example, the blinking patterns for normal code and
codes 11 and 21 are shown on the left.
(5) Codes are explained in the code table on page
DI±497.
(6) After completing the check, disconnect terminals Tc
and E
1, and turn off the display.
If 2 or more malfunctions are indicated at the same time the low-
est numbered DTC will be displayed 1st.
Page 1706 of 4592
H07517
TOYOTA
Hand±held Tester
DLC2
BR3890
F00006DLC1Short Pin
N09348
Hand±held Tester
Break±out±boxECUTOYOTA
TOYOTA DI±494
± DIAGNOSTICSANTI±LOCK BRAKE SYSTEM (DENSO Made)
729 Author: Date:
(c) Using TOYOTA hand±held tester, check the DTC.
(1) Hook up the TOYOTA hand±held tester to the
DLC2.
(2) Read the DTC by following the prompts on the tes-
ter screen.
Please refer to the TOYOTA hand±held tester oper-
ator 's manual for further details.
(d) Clear the DTC.
(1) Using SST, connect terminals Tc and E
1 of DLC2 or
DLC1 and remove the short pin from DLC1.
SST 09843 ± 18020
(2) Turn the ignition switch ON.
(3) Clear the DTC stored in ECU by depressing the
brake pedal 8 or more times within 5 seconds.
(4) Check that the warning light shows the normal
code.
(5) Remove the SST from the terminals of DLC2 or
DLC1.
SST 09843 ± 18020
(6) Connect the short pin to DLC1.
(e) Using TOYOTA break±out±box and TOYOTA hand±held
tester, measure the ECU terminal values.
(1) Hook up the TOYOTA hand±held tester and
TOYOTA break±out±box to the vehicle.
(2) Read the ECU input/output values by following the
prompts on the tester screen.
HINT:
TOYOTA hand±held tester has a ºSnapshotº function. This re-
cords the measured values and is effective in the diagnosis of
intermittent problems.
Please refer to the TOYOTA hand±held tester/TOYOTA break±
out±box operator's manual for further details.
Page 1707 of 4592
F02201
DLC1
TsTc E1
BR3904
0.13 sec. 0.13 sec.
ON
OFF
BR3893
Malfunction Code (Example Code 72, 76)
72 67
ON
OFF
0.5 sec. 0.5 sec. 0.5 sec. 0.5 sec.1.5 sec.
2.5 sec.4 sec.
Repeat
± DIAGNOSTICSANTI±LOCK BRAKE SYSTEM (DENSO Made)
DI±495
730 Author: Date:
2. SPEED SENSOR SIGNAL
(a) Check the speed sensor signal.
(1) Turn the ignition switch OFF.
(2) Using SST, connect terminals Ts and E
1 of DLC1.
SST 09843 ± 18020
(3) Start the engine.
(4) Check that the ABS warning light blinks.
HINT:
If the ABS warning light does not blink, inspect the ABS warning
light circuit (See page DI±529).
(5) Drive vehicle straight forward.
HINT:
Drive vehicle faster than 45 km/h (28 mph) for several seconds.
(6) Stop the vehicle.
(7) Using SST, connect terminals Tc and E
1 of DLC1.
SST 09843 ± 18020
(8) Read the number of blinks of the ABS warning light.
HINT:
See the list of DTC shown on the next page.
If every sensor is normal, a normal code is output (A cycle
of 0.25 sec. ON and 0.25 sec. OFF is repeated).
If 2 or more malfunctions are indicated at the same time,
the lowest numbered code will be displayed 1st.
(9) After doing the check, disconnect the SST from ter-
minals Ts and E
1, Tc and E1 of DLC1, and turn igni-
tion switch OFF.
SST 09843 ± 18020
Page 1708 of 4592
H07517
TOYOTA
Hand±held Tester
DLC2 DI±496
± DIAGNOSTICSANTI±LOCK BRAKE SYSTEM (DENSO Made)
731 Author: Date:
(b) Using TOYOTA hand±held tester, check the DTC.
(1) Do step 1. ~ 6. on the previous page.
(2) Hook up the TOYOTA hand±held tester to the
DLC2.
(3) Read the DTC by following the prompts on the tes-
ter screen.
Please refer to the TOYOTA hand±held tester oper-
ator 's manual for further details.
DTC of speed sensor check function:
Code No.DiagnosisTrouble Area
71Low output voltage of right front speed sensor
Right front speed sensor
Sensor installation
Right front speed sensor rotor
72Low output voltage of left front speed sensor
Left front speed sensor
Sensor installation
Left front speed sensor rotor
73Low output voltage of right rear speed sensor
Right rear speed sensor
Sensor installation
Right rear speed sensor rotor
74Low output voltage of left rear speed sensor
Left rear speed sensor
Sensor installation
Left rear speed sensor rotor
75Abnormal change in output voltage of right front speed sen-
sorRight front speed sensor rotor
76Abnormal change in output voltage of left front speed
sensorLeft front speed sensor rotor
77Abnormal change in output voltage of right rear speed
sensorRight rear speed sensor rotor
78Abnormal change in output voltage of left rear speed sensorLeft rear speed sensor rotor
Page 1709 of 4592
DI03D±03
± DIAGNOSTICSANTI±LOCK BRAKE SYSTEM (DENSO Made)
DI±497
732 Author: Date:
DIAGNOSTIC TROUBLE CODE CHART
HINT:
Using SST 09843 ±18020, connect the terminals Tc and E1, and remove the short pin.
If any abnormality is not found when inspection parts, inspect the ECU.
If a malfunction code is displayed during the DTC check, check the circuit listed for the code. For details
of each code, turn to the page referred to under the ºSee pageº for respective ºDTC No.º in the DTC
chart.
DTC No.
(See Page)Detection ItemTrouble Area
11
(DI±502)Open circuit in ABS solenoid relay circuitABS solenoid relay
12
(DI±502)Short circuit in ABS solenoid relay circuit
ABS solenoid relay
ABS solenoid relay circuit
13
(DI±507)Open circuit in ABS motor relay circuitABS motor relay
14
(DI±507)Short circuit in ABS motor relay circuit
ABS motor relay
ABS motor relay circuit
21
(DI±511)Open or short circuit in 2±position solenoid circuit for right front
wheelABS actuator
SFRR or SFRH circuit
22
(DI±511)Open or short circuit in 2±position solenoid circuit for left front
wheelABS actuator
SFLR or SFLH circuit
23
(DI±511)Open or short circuit in 2±position solenoid circuit for right rear
wheelABS actuator
SRRR or SRRH circuit
24
(DI±511)Open or short circuit in 2±position solenoid circuit for left rear
wheelABS actuator
SRLR or SRLH circuit
31
(DI±514)Right front wheel speed sensor signal malfunction
32
(DI±514)Left front wheel speed sensor signal malfunctionRight front, left front, right rear and left rear speed sensor
Eh d i it33
(DI±514)Right rear wheel speed sensor signal malfunction
Each speed sensor circuit
Speed sensor rotor
34
(DI±514)Left rear wheel speed sensor signal malfunction
33, 34
(DI±519)Rear speed sensor rotor faulty
Rear axle hub
Right rear, left rear speed sensor
Rear speed sensor circuit
41
(DI±520)Power source voltage down
Battery
Charging system
Power source circuit
49
(DI±523)Open circuit in stop light switch circuitStop light switch
Stop light switch circuit
51
(DI±525)Pump motor is lockedABS pump motor
Always ON
(DI±527)Malfunction in ECUECU
Battery
