Last Modified: 04-05-2023 |
6.11:8.1.0 |
Doc ID: RM100000000VIZO |
Model Year Start: 2016 |
Model: Sienna |
Prod Date Range: [12/2015 - 08/2016] |
Title: POWER ASSIST SYSTEMS: POWER STEERING SYSTEM: PS Warning Light Remains ON; 2016 MY Sienna [12/2015 - 08/2016] |
PS Warning Light Remains ON
|
DESCRIPTION
If the power steering ECU detects a malfunction, the EPS warning light comes on. At this time, the power steering ECU stores a DTC in its memory.
Also if the battery is not sufficiently charged or the voltage decreases temporarily, the amount of power assist may be reduced and the EPS warning light may come on.
WIRING DIAGRAM
CAUTION / NOTICE / HINT
NOTICE:
-
When the steering column assembly is replaced, perform the assist map writing (See page
).
-
Inspect the fuses for circuits related to this system before performing the following inspection procedure.
PROCEDURE
(a) Check for DTCs for power steering system (See page
).
Result
Result
|
Proceed to
|
DTCs are not output
|
A
|
DTCs are output
|
B
|
A
|
|
|
2.
|
READ VALUE USING TECHSTREAM (BATTERY VOLTAGE LO RECORD)
|
(a) Connect the Techstream to the DLC3.
(b) Turn the ignition switch to ON.
(c) Turn the Techstream on.
(d) Enter the following menus: Chassis / EMPS / Data List.
(e) In accordance with the display on the Techstream, read the Data List.
EMPS
Tester Display
|
Measurement Item/Range
|
Normal Condition
|
Diagnostic Note
|
Battery Voltage Lo Record
|
Battery voltage reduction history
Minimum: 0 times, Maximum: 65535 times
|
0 times
|
-
|
OK:
"Battery Voltage Lo Record" is 0 times.
OK
|
|
|
3.
|
CHECK CAN COMMUNICATION SYSTEM
|
(a) Check for DTCs of the CAN communication system (See page
).
Result
Result
|
Proceed to
|
DTCs are not output
|
A
|
DTCs are output
|
B
|
A
|
|
|
4.
|
PERFORM ACTIVE TEST USING TECHSTREAM (INDICAT EPS)
|
(a) Connect the Techstream to the DLC3.
(b) Start the engine.
(c) Turn the Techstream on.
(d) Enter the following menus: Body Electrical / Combination Meter / Active Test.
(e) Check that the EPS warning light operates in accordance with the Active Test.
Combination Meter
Tester Display
|
Test Part
|
Control Range
|
Diagnostic Note
|
Indicat. EPS
|
EPS warning light
|
OFF or ON
|
Confirm that the vehicle is stopped with the engine idling
|
OK:
The EPS warning light operation normally.
OK
|
|
|
5.
|
CHECK HARNESS AND CONNECTOR (STEERING COLUMN ASSEMBLY - BATTERY AND BODY GROUND)
|
(a) Disconnect the connector from the steering column assembly (power steering ECU).
(b) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
Tester Connection
|
Condition
|
Specified Condition
|
D36-1 (PIG) - Body ground
|
Always
|
11 to 14 V
|
|
|
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection
|
Condition
|
Specified Condition
|
D36-2 (PGND) - Body ground
|
Always
|
Below 1 Ω
|
*a
|
Front view of wire harness connector:
(to Steering Column Assembly (Power Steering ECU))
|
NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR
|
OK
|
|
|
6.
|
CHECK HARNESS AND CONNECTOR (STEERING COLUMN ASSEMBLY - IG POWER SUPPLY)
|
(a) Turn the ignition switch to ON.
(b) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
Tester Connection
|
Switch Condition
|
Specified Condition
|
D35-5 (IG) - Body ground
|
Ignition switch ON
|
11 to 14 V
|
*a
|
Front view of wire harness connector:
(to Steering Column Assembly (Power Steering ECU))
|
|
|
NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR
|
|