The 4WD vehicle measures
the G-sensor signal to solve for 4WD vehicle unique problems. For example
all 4 wheels are locked early on a low-friction road or control rESConse
is delayed when road friction coefficients vary.
The HECU uses a filtered
signal, as a supplementary value, to determine the road friction
coefficient. This value is used for the accurate calculations of assumed
vehicle speed, or precise division of control starting
points.
The HECU monitors the
G-sensor voltage continuosly,and sets this code if the G-sensor value is
either higher than 0.5G for more than 20 seconds when vehicle speed is
above 10 Km/h and brake switch is OFF, or if G-sensor value is lower than
0.1G for more than 60 seconds when wheel sensor minimum value is above
0.2G.
Item
|
Detecting
Condition
|
Possible cause
|
DTC
Strategy
|
|
| •
|
Improper installation of
G-Sensor |
| •
|
Abnormal Rotor and wheel
bearing |
|
Enable
Conditions
|
| •
|
When vehicle speed is >10km/h and the
brake light switch is off, |G|>0.5G for 20sec
continuously. |
| •
|
When |min wheel speed| / dt ≥0.2G and
|G| ≤0.1G for
60sec
continuously. | |
Fail
Safe
|
| •
|
ABS/ESC functions are inhibited, EBD
function is allowed and the ABS/ESC warning lamps are
activated. | |
| 1. |
Connect scantool to Data Link
Connector(DLC) |
| 2. |
Ignition "ON" & Engine
"OFF". |
| 3. |
Start and drive vehicle in gear and maintain
vehicle speed is approx. 10km/h or more (6mph or more) and then
accelerate and decelerate the vehicle several
times. |
| 4. |
Monitor the "G-sensor" parameter on the
Scantool.
Specification
: Below 0.4G (at a uniform
speed)
It is a normal condition if the data is
changed while accelerating or decelerating the
vehicle.
|
|
| 5. |
Is parameter displayed within
specifications?
|
|
▶ Fault is
intermittent caused by poor connection in G sensor harness
and/or HECU's connector or was repaired and HECU memory was
not cleared.
Thoroughly check
connectors for looseness, poor connection, bending, corrosion,
contamination, deterioration, or damage.
Repair or replace as necessary and then go to
"Verification Of Vehicle Repair" procedure.
|
|
|
▶ Go to
"Terminal and Connector Inspection"
procedure.
|
|
| Terminal and Connector
Inspection |
| 1. |
Many malfunctions in the electrical system are
caused by poor harness(es) and terminal condition. Faults can also
be caused by interference from other electrical systems, and
mechanical or chemical damage. |
| 2. |
Thoroughly check connectors for looseness,
poor connection, bending, corrosion, contamination, deterioration,
or damage. |
| 3. |
Has a problem been found?
|
|
▶ Repair as
necessary and then go to "Verification Of Vehicle Repair"
procedure.
|
|
|
▶ Go to
"Component Inspection"
procedure.
|
|
G Sensor Check
| 1. |
Check installation condition of G-sensor. If
NG, repair as necessary and go to "Verification Of Vehicle Repair"
procedure. |
| 2. |
Check damage of rotor teeth or wheel bearing.
If NG, repair as necessary and go to "Verification Of Vehicle
Repair" procedure. |
| 3. |
Ignition "ON" & Engine
"OFF". |
| 4. |
Measure waveform between signal terminal of
the G sensor harness connector and chassis ground with
osciloscope.
Specification
: Approx. 2.5V
0.3V ~ 4.7V (acceleration or
deceleration)
| |
| 5. |
Is the measured waveform within
specifications?
|
|
▶ Fault is
intermittent caused by poor connection in G sensor harness
and/or HECU's connector.
Go to
"Verification Of Vehicle Repair" procedure.
|
|
|
▶
Substitute with a known-good G sensor and check for proper
operation.
If problem is corrected,
replace G sensor and then go to "Verification Of Vehicle
Repair"
procedure.
|
|
| Verification of Vehicle
Repair |
After a repair, it is
essential to verify that the fault has been corrected.
| 1. |
Connect scantool and select "Diagnostic
Trouble Codes(DTCs)" mode. |
| 2. |
Using a scantool, Clear
DTC. |
| 3. |
Operate the vehicle within DTC Detecting
Condition in General Information. |
| 4. |
Using a scantool, Check DTC
present. |
| 5. |
Are any DTCs present ?
|
|
▶ Go to the
applicable troubleshooting procedure.
|
|
|
▶ System
performing to specification at this
time.
|
|
