Downloaded from www.Manualslib.com manuals search engine Power Assisted Steering System: 6C-15
“EPS” Warning Light Does Not Come ON with Ignition Switch Turned ON before Engine StartsS7RS0B6304010
Wiring Diagram
Circuit Description
Operation (ON/OFF) of “EPS” warning light is controlled by P/S control module through combination meter.
If the P/S system is in good condition, P/S control module turns “ EPS” warning light ON at the ignition switch ON, and
then turns it OFF at the engine start. If an abnormality in the system is detected, “EPS” warning light is turned ON
continuously by P/S control module. If P/S control module is disconnected, “EPS” warning light is not turned ON.
Troubleshooting
MBLK
REDE51-1
E51-2
[A ]
12 3
4 5 67
89
11
10
12 13
141516
17 18 19 2010 9 8 7654 3 21
16 15 14 13 12 11
26 25 24 2322 21 20 19 18 17
32 31 30 29 28 27
[C]
7
12V
E49-2BLK
[B ]
1 2
GRY
LT GRN
/BLK
E52-1
E52-5
E49-1
GRNGRNWHTBLK
WHY
G28-25G28-31
RED/BLK
8
3
4
4
5 6
4
4
1 2
4
9
I7RS0B630004-01
[A]: Connector “E52” (viewed from harness side) 2. Ignition switch6. “EPS” warning light
[B]: Connector “E49” (viewed from harness side) 3. Junction block assembly7. P/S control module
[C]: Connector “G28” (viewed from harness si de)4. Fuse 8. Individual circuit fuse box No.1
1. Main fuse box 5. Combination meter9. “EPS” warning light circuit
StepAction YesNo
1 1) Turn ignition switch ON.
Do the other warning lights come on? Go to Step 2.
“GRN”, “RED/BLK” wire
circuit or circuit fuse for
combination meter open
or short to ground.
2 1) Check power supply circuit and ground circuit for P/S control module referring to “P/S Control Module Power
Supply and Ground Circuit Check”.
Is check result in good condition? Go to Step 3.
Repair or replace
defective circuit.
3 1) Remove combination meter and disconnect combination meter connector (“G28”) with ignition switch turned OFF.
2) Check for proper connection to the combination meter at “G28-31” terminal.
3) If OK, check voltage between “G28-31” (“RED/BLK” wire) terminal and body ground with ignition switch ON.
Is it 10 – 14 V? Go to Step 4.
“RED/BLK” wire circuit
open or short to ground.
Downloaded from www.Manualslib.com manuals search engine Power Assisted Steering System: 6C-19
DTC C1114: Steering Torque Sensor Reference Power Supply CircuitS7RS0B6304013
Wiring Diagram
DTC Detecting Condition and Trouble Area
M
5V
BLK
RED
WHT BLU
GRN
BRN YEL
E51-1
E51-2
E52-18
E53-5
E53-7
E52-6
E52-8
E53-2
E52-9
E52-16
E52-19
GRY
5
67
12V
5V
5V
12V
REDE52-20E53-6
E53-4
E53-1
9[A ]
12 3
4 5 67
89
11
10
12 13
141516
17 18 19 20
1
2
[B ]
[C ]
7654321
LT GRN
/BLKE52-1 E49-1
GRNGRNWHTBLK
WHY
8
3
4
4
4
4
1 2
E49-2BLK
I7RS0B630006-01
[A]: Connector “E52” (viewed from harness side)
2. Ignition switch6. Torque sensor
[B]: Connector “E49” (viewed from harness side) 3. Junction block assembly 7. Torque sensor amplifier
[C]: Connector “E53” (viewed from harness si de)4. Fuse 8. Individual circuit fuse box No.1
1. Main fuse box 5. P/S control module9. Torque sensor 5 V reference power supply circuit
DTC detecting condition Trouble area
Circuit voltage of torque sensor 5 V reference power
supply voltage is more than 5.7 V or less than 4.3 V for 1
second continuously
(1 driving cycle detection logic) • Torque sensor circuit
• Torque sensor
• P/S control module
Downloaded from www.Manualslib.com manuals search engine 6C-20 Power Assisted Steering System:
DTC TroubleshootingStep Action Yes No 1 Was “EPS System Check” performed? Go to Step 2. Go to “EPS System
Check”.
2 DTC check
Is DTC C1153 and/or DTC C1155 indicated together? Go to applicable DTC
diag. flow.
Go to Step 3.
3 Torque sensor 5 V reference power supply circuit
voltage check
1) With ignition switch turned OFF, disconnect torque
sensor connector and check for proper terminal
connection to torque sensor connector.
2) If connections are OK, check for voltage between “E53- 6” (“RED” wire) terminal and body ground with ignition
switch ON.
Is it approx. 5 V? Go to Step 4. Go to Step 5.
4 Torque sensor 5 V reference power supply circuit check
1) With ignition switch turned OFF, connect torque sensor
connector.
2) Check for P/S control module connector (“E52”) for proper connection.
3) Turn ignition switch ON.
4) Check for voltage between “Torque sensor 5 V reference power supply circuit” terminal and body ground with
connector (“E52”) connected to the P/S control module.
Is it about 5 V? Substitute a known-
good P/S control
module and recheck.
Replace steering gear
case.
5 Torque sensor 5 V reference power supply circuit check
1) With ignition switch turned OFF, disconnect P/S control
module connector.
2) Check that “Torque sensor 5 V reference power supply circuit” is as following.
• Insulation resistance of “Torque sensor 5 V reference power supply circuit” wire is infinity between its
terminal and other terminal at torque sensor
connector.
• Wiring resistance of “Torque sensor 5 V reference power supply circuit” is less than 1 Ω.
• Insulation resistance of “Torque sensor 5 V reference power supply circuit” between its circuit and vehicle
body ground is infinity.
Is circuit in good condition? Replace P/S control
module.
Repair or replace
defective circuit.
20
E52
I4RS0A630013-02
Downloaded from www.Manualslib.com manuals search engine 6C-24 Power Assisted Steering System:
DTC C1119: Steering Torque Sensor Power Supply CircuitS7RS0B6304016
Wiring Diagram
DTC Detecting Condition and Trouble Area
M
5V
BLK
RED
WHT BLU
GRN
BRN YEL
E51-1
E51-2
E52-18
E53-5
E53-7
E52-6
E52-8
E53-2
E52-9
E52-16
E52-19
GRY
5
67
12V
5V
5V
12V
REDE52-20E53-6
E53-4
E53-1
9
[A ]
12 3
4 5 67
89
11
10
12 13
141516
17 18 19 20
1
2
[B ]
[C ]
7654321
LT GRN
/BLKE52-1 E49-1
GRNGRNWHTBLK
WHY
8
3
4
4
4
4
1 2
E49-2BLK
I7RS0B630008-01
[A]: Connector “E52” (viewed from harness side)
2. Ignition switch6. Torque sensor
[B]: Connector “E49” (viewed from harness side) 3. Junction block assembly7. Torque sensor amplifier
[C]: Connector “E53” (viewed from harness si de)4. Fuse 8. Individual circuit fuse box No.1
1. Main fuse box 5. P/S control module9. Main power supply for torque sensor circuit
DTC detecting condition Trouble area
Circuit voltage of torque sensor main power supply is less
than 7.5 V for 1 second continuously
(1 driving cycle detection logic) • Torque sensor circuit
• Torque sensor
• P/S control module
Downloaded from www.Manualslib.com manuals search engine Power Assisted Steering System: 6C-25
DTC TroubleshootingStep Action Yes No 1 Was “EPS System Check” performed? Go to Step 2. Go to “EPS System
Check”.
2 DTC check
Is DTC C1153 indicated together? Go to DTC C1153 diag.
flow.
Go to Step 3.
3 Torque sensor main power supply voltage check
1) With ignition switch turned OFF, disconnect torque
sensor connector.
2) Check for P/S control module connector (“E52”) for proper connection.
3) If connections are OK, check for voltage between “E52- 8” (“GRN” wire) terminal and body ground with ignition
switch ON.
Is it approx. 12 V? Go to Step 4. Go to Step 5.
4 Torque sensor main power supply voltage check
1) With ignition switch turned OFF, connect torque sensor
connector.
2) Check for P/S control module connector (“E52”) for proper connection.
3) Turn ignition switch ON.
4) Check for voltage between “Main power supply for torque sensor circuit” terminal and body ground with
connector (“E52”) connected to the P/S control module.
Is it about 12 V? Substitute a known-
good P/S control
module and recheck.
Replace steering gear
case assembly and
recheck.
5 Torque sensor main power supply circuit check
1) With ignition switch turned OFF, disconnect P/S control
module connector.
2) Check that “Main power supply for torque sensor circuit” is as following.
• Insulation resistance of “Main power supply for torque sensor circuit” wire is infinity between its terminal and
other terminal at torque sensor connector.
• Wiring resistance of “Main power supply for torque sensor circuit” is less than 1 Ω .
• Insulation resistance of “Main power supply for torque sensor circuit” between its circuit and vehicle body
ground is infinity.
Is circuit in good condition? Replace P/S control
module.
Repair or replace
defective circuit.
8
E52
I4RS0A630021-02
Downloaded from www.Manualslib.com manuals search engine Power Assisted Steering System: 6C-31
DTC Detecting Condition and Trouble Area
DTC TroubleshootingDTC detecting condition Trouble area
DTC C1141:
Voltage between both motor drive circuits is more than 8.5
V or less than 0.2 V for 0.5 seconds continuously while
motor is not drived
(1 driving cycle detection logic)
DTC C1142:
Measured motor drive current is more than 10 A as
compared with target motor drive current.
(1 driving cycle detection logic)
DTC C1143:
Measured motor drive current is more than 50 A.
(1 driving cycle detection logic)
DTC C1145:
Measured motor drive current is less than 2 A
continuously for more than 3 seconds even though target
motor drive current is more than 4 A.
or
Measured motor drive current is less than 0.8 A for total 1
second even though motor cont rol duty is more than 90%
while target motor drive current is less than 8 A.
(1 driving cycle detection logic) • P/S motor circuit
• P/S motor
• P/S control module
Step
Action YesNo
1 Was “EPS System Check” performed? Go to Step 2.Go to “EPS System
Check”.
2 DTC check
Is DTC C1153 and/or DTC C1155 indicated together? Go to applicable DTC
diag. flow.
Go to Step 3.
3 Power supply and ground circuit check
1) Check P/S control module power supply and ground
circuit referring to “P/S Control Module Power Supply
and Ground Circuit Check”.
Is it in good condition? Go to Step 4.
Repair or replace
defective circuit.
4 Motor circuit check
1) With ignition switch tuned OFF, disconnect P/S motor
connector (“E51”).
2) Check that P/S motor circuit is as follows. • Insulation resistance of wire harness is infinity between each “P/S motor circuit” terminal and other
terminal at P/S motor connector.
• Wiring harness resistance of each “P/S motor circuit”
is less than 1 Ω.
• Insulation resistance between each “P/S motor circuit” and vehicle body ground is infinity.
• Circuit voltage between each “P/S motor circuit” and ground circuit is 0 – 1 V with ignition switch turned
ON.
Is circuit in good condition? Go to Step 5.
Repair or replace
defective circuit.
5 P/S motor check
1) Check motor and its circuit referring to “P/S Motor and Its
Circuit Inspection”.
Is motor in good condition? Substitute a known-
good P/S control
module, and recheck.
Replace the steering
gear case assembly.
Downloaded from www.Manualslib.com manuals search engine 6C-32 Power Assisted Steering System:
DTC C1153: P/S Control Module Power Supply Circuit Voltage LowS7RS0B6304020
Wiring Diagram
DTC Detecting Condition and Trouble Area
DTC Troubleshooting
MBLK
REDE51-1
E51-2
12V
5
[A ]
12 3
4 5 67
89
11
10
12 13
141516
17 18 19 20
[B ]
1
2
LT GRN
/BLKE52-1 E49-1
GRNGRNWHTBLK
WHY
6
3
4
4
4
4
1 2
E49-2BLK
I7RS0B630011-01
[A]: Connector “E52” (viewed from harness side)
2. Ignition switch5. P/S control module
[B]: Connector “E49” (viewed from harness side) 3. Junction block assembly 6. Individual circuit fuse box No.1
1. Main fuse box 4. Fuse
DTC detecting condition Trouble area
Power supply voltage of P/S control module is less than 9
V for 5 seconds continuously
(1 driving cycle detection logic) • P/S control module power supply circuit
• Undercharged Battery
• P/S control module
Step
Action YesNo
1 Was “EPS System Check” performed? Go to Step 2.Go to “EPS System
Check”.
2 Battery voltage check
1) Check circuit fuse for P/S control module.
2) If OK, measure voltage between positive battery terminal
and vehicle body ground with engine running.
Is voltage 10 V or more? Go to Step 3.
Check charging system
referring to “Generator
Test (Undercharged
Battery Check) in
Section 1J”.
3 P/S control module power supply circuit check
1) Check power supply circuit and ground circuit for P/S
control module referring to “P/S Control Module Power
Supply and Ground Circuit Check”.
Is check result in good condition? Substitute a known-
good P/S control
module and recheck.
Repair defective circuit.
Downloaded from www.Manualslib.com manuals search engine Power Assisted Steering System: 6C-33
DTC C1155: P/S Control Module FailureS7RS0B6304021
Wiring Diagram
Refer to “DTC C1153: P/S Control Module Power Supply Circuit Voltage Low”.
DTC Detecting Condition and Trouble Area
DTC Troubleshooting DTC detecting condition Trouble area
Internal memory (EEPROM) is data error.
(In this case, MIL does not light up)
or
Internal circuit is faulty.
or
Power supply voltage of P/S control module exceeded
17.5 V.
(1 driving cycle detection logic) • Overcharged Battery
• P/S control module
Step
Action YesNo
1 Was “EPS System Check” performed? Go to Step 2.Go to “EPS System
Check”.
2 P/S control module power supply and ground circuit
check
Check power supply circuit and ground circuit for P/S control
module referring to “P/S Control Module Power Supply and
Ground Circuit Check”.
Is check result in good condition? Go to Step 3.
Repair or replace
defective circuit.
3 Battery voltage check
1) Check voltage between positive (+) battery terminal and
vehicle body ground with engine speed at 3000 rpm.
Is voltage 15.5 V or less? Replace P/S control
module.
Check charging system
referring to “Generator
Test (Overcharged
Battery Check) in
Section 1J”.