Bendix Commercial Vehicle Systems TABS-6 ADVANCED SINGLE CHANNEL - Manual (Page 32)

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SECTION F: TROUBLESHOOTING THE
LOAD SENSOR (OUT‑OF‑RANGE CONDITION)
(Note: The indicator lamp for this condition is illuminated only after the vehicle moves.)
Turn off the power to the module.
For spring suspension system trailers:
Verify/inspect the following:
1. Inspect the load sensor linkage:
• Check that the linkage is attached to the axle clamp.
• Inspect for damage to the linkage components,
loose connectors and mis‑installation.
• Check that the load sensor lever rod is in a
horizontal position with the trailer empty.
• Verify that the sensor linkage has not flipped over
so that it faces the opposite direction.
2. Switch on power to the module. Using Bendix ®
ACom ® Diagnostics, open the TRSP Sensors
screen and select “Start.” Find the load (in lbs.) that
the sensor is registering, and verify that the actual
trailer load is consistent with the value found.
3. Where the value does not appear to be correct,
perform the load sensor resistance check:
• Unplug the 18-pin connector from the module.
• With the load sensor lever in the horizontal position,
verify that approximately 2.5K Ohms is measured
between pins four (4) and nine (9) and between
pins nine (9) and ten (10). Using Bendix ACom
Diagnostics open the configuration screen. Select
the Load and Sensor Configuration tab, and then
view the “Load Sensing” panel. Verify that the
current “Sensing Type” is shown as “External.” If
not, change the selection to “External.”
• Note the values shown on the screen for the current
load and sensor voltage. Verify that the values
shown on the screen for the empty and laden
weight and voltage are correct.
Where the value does not appear to be correct,
enter the correct value(s) on the configuration
screen. If your version of Bendix ACom Diagnostics
does not permit you to make these changes, update
your copy of the program (available as a free
download from the support pages at www.bendix.
com.)
Note: Use a scale to obtain the actual empty trailer
weight. Where possible, obtain the load/deflection curve
from the suspension/spring manufacturer for the specific
suspension/spring combination to find the expected
values for this vehicle.
Then rerun the power up sequence. Go to Section A.
For air suspension system trailers:
Verify/inspect the following:
1. Check that port P42 is connected by an unkinked
air hose to the primary suspension air bags.
2. Check that the suspension height control valve is
functioning correctly.
3. Check for air leakage in the suspension system.
4. Switch on power to the module. Using Bendix
®
ACom ® Diagnostics, open the TRSP Sensors
screen and select “Start.” Find the load (in lbs.)
that the sensor is registering, and verify that the
actual trailer load is consistent with the value
found.
5. Where the value does not appear to be correct,
using Bendix ACom Diagnostics, open the
“Pressures” screen and select “Start.” Read the
pressure shown for the airbag port (P42). If the
pressure value is not as expected, open the
“Configuration” screen; then select the Load and
Sensor Configuration tab, and then view the
“Load Sensing” panel. Verify that the current
“Sensing Type” is shown as “Internal.” If not,
change the selection to “Internal.”
Note the values shown on the screen for the
current load and pressure. Verify that the values
shown on the screen for the empty and laden
weight and pressures are correct.
Where the value does not appear to be correct,
select “modify”, and enter the correct value(s)
on the configuration screen. If your version of
Bendix ACom Diagnostics does not permit you
to make these changes, update your copy of the
program (available as a free download from the
support pages at www.bendix.com.)
Note: Use a scale to obtain the actual empty trailer
weight and use a pressure gauge to obtain actual
empty trailer suspension air bag pressure. Where
possible, obtain the load/pressure curve from the
suspension manufacturer for the specific suspension/
air bag combination to find the expected values for
this vehicle.
Then rerun the power up sequence. Go to Section A.