Actron GM Code Scanner CP9001 - Manual (Page 94)

94
29
All Wheel Speed Sensor
Voltage Output Signals
are erratic. Trouble code 29
is usually caused by an
improperly seated 8 way
connector at the EHCU
(Electro-Hydraulic Control
Unit). Check for corrosion or
dirty contacts, and that the
connector is properly
installed in the EHCU.
31
Right Rear Wheel Speed
Sensor Circuit resistance
is incorrect. This code is
indicative of high resistance
in this particular wheel
speed sensor circuit. The
resistance of the wheel
speed sensor may be out of
specification, or there may
be loose, corroded, or dirty
connections in this circuit.
32
Right Rear Wheel Speed
Sensor Voltage Output is
incorrect. This code
indicates a problem in the
wheel speed sensor or its
associated tone (toothed)
wheel. Check for the proper
air gap between the wheel
speed sensor and tone
wheel, missing or broken
teeth on the tone wheel, a
loose, improperly mounted,
or mis-adjusted wheel speed
sensor. An intermittent
connection in the associated
wiring can also set this
code.
33
Right Rear Wheel Speed
Sensor Voltage Output is
erratic. Erratic voltage
output usually indicates a
loose, dirty, or corroded
connection.Check the
connections at the wheel
speed sensor connector, the
wheel speed sensor
harness, and the EHCU
(Electro-Hydraulic Control
Unit). There may also be a
problem in the wheel speed
sensor or its associated
tone (toothed) wheel. Check
for the proper air gap
between the wheel speed
sensor and tone wheel,
missing or broken teeth on
the tone wheel, a loose,
improperly mounted, or mis-
adjusted wheel speed
sensor
35
Left Rear Wheel Speed
Sensor Circuit resistance
is incorrect. This code is
indicative of high resistance
in this particular wheel
speed sensor circuit. The
resistance of the wheel
speed sensor may be out of
specification, or there may
be loose, corroded, or dirty
connections in this circuit.
36
Left Rear Wheel Speed
Sensor Voltage Output is
incorrect. This code
indicates a problem in the
wheel speed sensor or its
associated tone (toothed)
wheel. Check for the proper
air gap between the wheel
speed sensor and tone
wheel, missing or broken
teeth on the tone wheel, a
loose, improperly mounted,
or mis-adjusted wheel speed
sensor. An intermittent
connection in the associated
wiring can also set this
code.
37
Left Rear Wheel Speed
Sensor Voltage Output is
erratic. Erratic voltage
output usually indicates a
loose, dirty, or corroded
connection. Check the
connections at the wheel
speed sensor connector, the
wheel speed sensor
harness, and the EHCU
(Electro-Hydraulic Control
Unit). There may also be a
problem in the wheel speed
sensor or its associated
tone (toothed) wheel. Check
for the proper air gap
between the wheel speed
sensor and tone wheel,
missing or broken teeth on
the tone wheel, a loose,
improperly mounted, or mis-
adjusted wheel speed
sensor.
38
Speed Sensor Voltage
Signal Output is erratic.
When this code appears, it is
usually accompanied with
code 23, 27, 33, or 37. If it is
accompanied with one or
more of the listed codes, use
the trouble chart for that code
to diagnose the system. If
trouble code 38 appears by
itself, all connections
between the wheel speed
sensors and the EHCU
(Electro-Hydraulic Control
Unit) will need to be checked
for looseness, dirt, corrosion,
etc
41
Right Front Isolation Valve
Solenoid, open circuit.
Double check to make sure
that the code has been
properly read. If it has, clear
all trouble codes by following
the ERASING ABS CODES
FROM COMPUTER
MEMORY procedure on
page 12-83. Thoroughly road
test the vehicle. Check for
trouble codes again. If this
code returns, the EHCU
(Electro-Hydraulic Control
Unit) is defective and should
be replaced. The EHCU is a
costly part! Your dealer may
offer an exchange policy in
which case your defective
unit has value (core credit)
towards the purchase of the
replacement. Securely
attach a tag to your defective
unit clearly indicating the
trouble code(s) reported by
the defective EHCU.
42
Right Front Pulse Width
Modulation Valve
Solenoid, open circuit.
Refer to the explanation
under trouble code 41.
43
Right Front Isolation Valve
Solenoid, short circuit.
Double check to make sure
that the code has been
properly read. Carefully
check all power and ground
connections at the EHCU. If
the code has been properly
read, and there are no
problems in the power or
ground circuits, clear all
trouble codes by following
the ERASING ABS CODES
FROM COMPUTER
MEMORY procedure on
page 12-83. Thoroughly road
test the vehicle. Check for
trouble codes again. If this
code returns, the EHCU
(Electro-Hydraulic Control
Unit) is defective and should
be replaced. The EHCU is a
costly part! Your dealer may
offer an exchange policy in
which case your defective
unit has value (core credit)
towards the purchase of the
replacement. Securely