Page 1801 of 2572

A67446
A62954A85537
4.5
to 5.5 V
0 V
Turn Wheel SPD (+) E1 (-)
E9
ECM
E6
ECM
05-218
- DIAGNOSTICSSFI SYSTEM (2AZ-FE)
408 Author: Date:
2005 HIGHLANDER REPAIR MANUAL (RM1144U)
INSPECTION PROCEDURE
HINT:
Read freeze frame data using the hand-held tester or the OBD II scan tool. Freeze frame data records the
engine conditions when a malfunction is detected. When troubleshooting, freeze frame data can help deter-
mine if the vehicle was running or stopped, if the engine was warmed up or not, if the air-fuel ratio was lean
or rich, and other data from the time the malfunction occurred.
1 CHECK OPERATION OF SPEEDOMETER
(a) Drive the vehicle and check if operation of the speedometer in the combination meter is normal.
HINT:
The vehicle speed sensor is operating normally if the speedometer display is normal.
NG CHECK SPEEDOMETER CIRCUIT
(See page 05-1885)
OK
2 INSPECT ECM (SPD VOLTAGE)
(a) Shift the lever to the neutral position.
(b) Jack up the vehicle.
(c) Turn the ignition switch ON.
(d) Measure the voltage of the ECM connectors as the wheel
is turned slowly.
Standard:
Tester ConnectionSpecified Condition
E6-17 (SPD) - E9-1 (E1)Generated intermittently
HINT:
The output voltage should fluctuate up and down similarly to the
diagram on the left when the wheel is turned slowly.
NG REPAIR OR REPLACE HARNESS AND
CONNECTOR
OK
REPLACE ECM (See page 10-9)
Page 1802 of 2572

- DIAGNOSTICSSFI SYSTEM (2AZ-FE)
05-219
409 Author: Date:
2005 HIGHLANDER REPAIR MANUAL (RM1144U)
DTC P0504 BRAKE SWITCH ºAº/ºBº CORRELATION
CIRCUIT DESCRIPTION
In addition to turning on the stop lamp, the stop lamp switch signals are used for a variety of engine, transmis-
sion, and suspension functions as well as being an input for diagnostic checks. It is important that the switch
operates properly, therefore this switch is designed with two complementary signal outputs: STP and ST1.
The ECM analyzes these signal outputs to detect malfunctions in the stop lamp switch.
HINT:
Normal condition is as shown in the table.
SignalBrake pedal releasedIn transitionBrake pedal depressed
STPOFFONON
ST1ONONOFF
DTC No.DTC Detection ConditionTrouble Area
P0504
Conditions (a), (b) and (c) continue for 0.5 seconds or more:
(a) Ignition switch ON
(b) Brake pedal released
(c) STP signal is OFF when the ST1 signal is OFFShort in stop lamp switch signal circuit
STOP fuse
Stop lamp switch
ECM
05EVK-05
Page 1803 of 2572
A90301
S15
Stop Lamp Switch Assy
19
E6
1 2
3
WSTP
ST1- 12
4
1C
7AM2IGN I15
Ignition Switch J6
J/C
AM2 STOP 1
EE6
IG21 1E
FL
Main 1
BR
E9
J7
J/C F7
FL Block Assy
ALT
1
EE 1
10
A
AE1
BatteryBR 2 BECM
Passenger Side J/B
E 1
1AInstrument
Panel J/B Assy
61G6 Instrument Panel J/B Assy
W1
IC1 L-Y
YGRP
4E1
4M4 PVBR B Y
4L3
4M12 Passenger Side J/B 05-220
- DIAGNOSTICSSFI SYSTEM (2AZ-FE)
410 Author: Date:
2005 HIGHLANDER REPAIR MANUAL (RM1144U)
WIRING DIAGRAM
Page 1804 of 2572

A82517
Free Pushed in
43 21
- DIAGNOSTICSSFI SYSTEM (2AZ-FE)
05-221
411 Author: Date:
2005 HIGHLANDER REPAIR MANUAL (RM1144U)
INSPECTION PROCEDURE
HINT:
Read freeze frame data using the hand-held tester or the OBD II scan tool. Freeze frame data records the
engine conditions when a malfunction is detected. When troubleshooting, freeze frame data can help deter-
mine if the vehicle was running or stopped, if the engine was warmed up or not, if the air-fuel ratio was lean
or rich, and other data from the time the malfunction occurred.
Hand-held tester:
1 CHECK STOP LAMP (OPERATION)
(a) Check if the stop lamps turn on and off normally when the brake pedal is depressed and released.
OK:
The stop lamps turn on when you depress the brake pedal.
NG REPAIR OR REPLACE STOP LAMP SWITCH
CIRCUIT
OK
2 INSPECT STOP LAMP SWITCH ASSY (RESISTANCE)
(a) Measure the resistance of the switch terminals.
Standard:
Switch ConditionTester ConnectionSpecified Condition
Switch pin free1 - 2Below 1.5 V
Switch pin free3 - 410 kW or higher
Switch pin pushed in1 - 210 kW or higher
Switch pin pushed in3 - 4Below 1.5 V
NG REPLACE STOP LAMP SWITCH ASSY
OK
Page 1805 of 2572
A72880
Brake Pedal
DepressedBrake Pedal
Released
ST1 (+) E1 (-)
E6
ECM
E9
ECM
05-222
- DIAGNOSTICSSFI SYSTEM (2AZ-FE)
412 Author: Date:
2005 HIGHLANDER REPAIR MANUAL (RM1144U)
3 READ VALUE OF HAND-HELD TESTER (STP SIGNAL, ST1 VOLTAGE)
(a) Turn the ignition switch ON.
(b) On the hand-held tester, enter the following menus:
DIAGNOSIS / ENHANCED OBD II / DATA LIST / ALL /
STOP LIGHT SW. Read the value.
Standard:
Brake Pedal ConditionSpecified Condition
DepressedSTP Signal ON
ReleasedSTP Signal OFF
(c) Measure the voltage of the ECM connectors.
Standard:
Tester ConnectionBrake Pedal ConditionSpecified Condition
E6-12 (ST1) - E9-1 (E1)DepressedBelow 1.5 V
E6-12 (ST1) - E9-1 (E1)Released7.5 to 14 V
OK CHECK FOR INTERMITTENT PROBLEMS
(See page 05-9)
NG
Page 1806 of 2572
Y
A56986
A67404
A87771
Wire Harness Side
S15
Stop Lamp Switch
STP E6
ECM
ST1
- DIAGNOSTICSSFI SYSTEM (2AZ-FE)
05-223
413 Author: Date:
2005 HIGHLANDER REPAIR MANUAL (RM1144U)
4 CHECK WIRE HARNESS (STOP LAMP SWITCH - ECM)
(a) Disconnect the S15 stop lamp switch connector.
(b) Disconnect the E6 ECM connector.
(c) Measure the resistance of the wire harness side connec-
tors.
Standard:
Tester ConnectionSpecified Condition
S15-1 - E6-19 (STP)
S15-4 - E6-12 (ST1)Below 1 W
S15-1 or E6-19 (STP) - Body ground
S15-4 or E6-12 (ST1) - Body ground10 kW or higher
NG REPAIR OR REPLACE HARNESS AND
CONNECTOR
OK
REPLACE ECM (See page 10-9)
OBD II scan tool (excluding hand-held tester):
1 CHECK STOP LAMP (OPERATION)
(a) Check if the stop lamps turn on and off normally when the brake pedal is depressed and released.
OK:
The stop lamps turn on when you depress the brake pedal.
NG REPAIR OR REPLACE STOP LAMP SWITCH
CIRCUIT
OK
Page 1807 of 2572
A82517
Free Pushed in
43 21
A72880
Brake Pedal
DepressedBrake Pedal
Released
ST1 (+)
E9
ECM E1 (-)
E6
ECM
STP (+)
05-224
- DIAGNOSTICSSFI SYSTEM (2AZ-FE)
414 Author: Date:
2005 HIGHLANDER REPAIR MANUAL (RM1144U)
2 INSPECT STOP LAMP SWITCH ASSY
(a) Measure the resistance of the switch terminals.
Standard:
Switch ConditionTester ConnectionSpecified Condition
Switch pin free1 - 2Below 1 W
Switch pin free3 - 410 kW or higher
Switch pin pushed in1 - 210 kW or higher
Switch pin pushed in3 - 4Below 1 W
NG REPLACE STOP LAMP SWITCH ASSY
OK
3 INSPECT ECM (STP, ST1 VOLTAGE)
(a) Turn the ignition switch ON.
(b) Measure the voltage of the ECM connectors.
Standard:
Tester ConnectionBrake Pedal ConditionSpecified Condition
E6-19 (STP) - E9-1 (E1)Depressed7.5 to 14 V
E6-19 (STP) - E9-1 (E1)ReleasedBelow 1.5 V
E6-12 (ST1) - E9-1 (E1)DepressedBelow 1.5 V
E6-12 (ST1) - E9-1 (E1)Released7.5 to 14 V
OK CHECK FOR INTERMITTENT PROBLEMS
(See page 05-9)
NG
Page 1808 of 2572
Y
A56986
A67404
A87771
Wire Harness Side
S15
Stop Lamp Switch
STP E6
ECM
ST1
- DIAGNOSTICSSFI SYSTEM (2AZ-FE)
05-225
415 Author: Date:
2005 HIGHLANDER REPAIR MANUAL (RM1144U)
4 CHECK WIRE HARNESS (STOP LAMP SWITCH - ECM)
(a) Disconnect the S15 stop lamp switch connector.
(b) Disconnect the E6 ECM connector.
(c) Measure the resistance of the wire harness side connec-
tors.
Standard:
Tester ConnectionSpecified Condition
S15-1 - E6-19 (STP)
S15-4 - E6-12 (ST1)Below 1 W
S15-1 or E6-19 (STP) - Body ground
S15-4 or E6-12 (ST1) - Body ground10 kW or higher
NG REPAIR OR REPLACE HARNESS AND
CONNECTOR
OK
REPLACE ECM (See page 10-9)