Power Steering ECU Communication Stop Mode
Detection Item | Symptom | Trouble Area |
|---|---|---|
Power Steering ECU Communication Stop Mode |
Either condition is met:
|
|
CAUTION / NOTICE / HINT
NOTICE:
Inspect the fuses for circuits related to this system before performing the following inspection procedure.
HINT:
Operating the ignition switch, any switches or any doors triggers related ECU and sensor communication with the CAN, which causes resistance variation.
PROCEDUREDISCONNECT CABLE FROM NEGATIVE BATTERY TERMINAL
(a) Disconnect the cable from the negative (-) battery terminal before measuring the resistances of the main wire and branch wire.
CAUTION:
Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.
NOTICE:
When disconnecting the cable, some systems need to be initialized after the cable is reconnected (See page
).
|
CHECK FOR OPEN IN CAN BUS WIRE (POWER STEERING ECU ASSEMBLY BRANCH WIRE)
(a) Disconnect the F41 power steering ECU assembly connector. |
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(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection | Switch Condition | Specified Condition |
|---|---|---|
F41-1 (CANH) - F41-2 (CANL) |
Ignition switch off |
54 to 69 Ω |
*a |
Rear view of wire harness connector (to Power Steering ECU Assembly) |
| NG | ![]() | REPAIR OR REPLACE POWER STEERING ECU ASSEMBLY BRANCH WIRE OR CONNECTOR (CANH, CANL) |
|
CHECK HARNESS AND CONNECTOR (POWER STEERING ECU ASSEMBLY - BATTERY AND BODY GROUND)
(a) Connect the cable to the negative (-) battery terminal. NOTICE: When disconnecting the cable, some systems need to be initialized after the cable is reconnected (See page |
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(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection | Condition | Specified Condition |
|---|---|---|
F41-3 (GND) - Body ground |
Always |
Below 1 Ω |
(c) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
Tester Connection | Switch Condition | Specified Condition |
|---|---|---|
F41-5 (IG) - Body ground |
Ignition switch ON |
11 to 14 V |
*a |
Rear view of wire harness connector (to Power Steering ECU Assembly) |
| OK | ![]() | REPLACE POWER STEERING ECU ASSEMBLY |
| NG | ![]() | REPAIR OR REPLACE HARNESS OR CONNECTOR |
Test yourself
A quick Toyota 4Runner quiz: every answer comes with an explanation and a link to the manual page.
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