Product Manual

10
3.3 AIR BRAKE CONTROL PANEL
A. Air Pressure Gauge - Emergency Side
B. Air Out to Red Hose - Emergency Side
C. Emergency Side Air Ball Valve
D. Air Regulator Knob
E. Air Pressure Gauge - Service Side
F. Service Side Brake Control Switch
G. Air Out to Blue Hose - Service Side
H. Service Side Air Ball Valve
Air Brake Control Panel
B
A
C
F
E
G
H
D
31
Fault
Code
Explanation
21
Red channel wheel speed
sensor S1A has an erratic
output voltage.
22
Red channel wheel speed
sensor S1B has an erratic
output voltage.
23
Blue channel wheel speed
sensor S2A has an erratic
output voltage
24
Yellow channel wheel speed
sensor S2B has an erratic
output voltage.
25
Blue channel wheel speed
sensor S3A has an erratic
output voltage.
26
Yellow channel wheel speed
sensor S3B has an erratic
output voltage.
Possible Causes
Loose sensor, connection ,
bracket or exciter, damaged
exciter, sensor is not prop-
erly adjusted or has worn cable
insulation, or worn sensor block
clip, wheel bearing failure,
wheel bearing is not properly
adjusted (these faults will only
occur at speeds greater than
6 mph).
Measure the AC voltage at the
sensor in question while rotating
the wheel at a rate of about one
rotation every two seconds. The
output should be at least 200
millivolts (0.2 VAC).
If this is not the case, push in
the sensor until it touches the
exciter and rotate the wheel
again. If this doesn’t correct the
problem, then the sensor should
be replaced.
Verify the tire and wheel size
is large enough for 100 tooth
exciter ring. If these faults
re-occur at the same speed,
inspect the exciter ring for
damage.
Smaller wheels and tires require
80 tooth exciter rings. Reference
Tire Scale Factor Chart.
Verify sensor and valve wiring/
plumbing is correct.
See side by side and axle by
axle confi gurations.
PLC
Select
1M
PLC
Select
2M
Occurs Only When Vehicle is Stationary
31
Auxiliary channel 1 fault (digi-
tal channel 1) output only
32
Auxiliary channel 2 fault (digi-
tal channel 2) output only
33
Auxiliary channel 3 fault (digi-
tal channel 3) output only
34
Auxiliary channel 4 fault (digi-
tal channel 4) output only
35
Auxiliary channel 5 fault (digi-
tal channel 5) output only
PLC Select 2M Plus (ABS
Auxiliary Codes)
Note:
These Codes are only used with
PLC Select 2M Plus ABS that
supports trailer Auxiliaries.
Auxiliary Channel has an open
circuit or the ECU (Electronic
Control Unit) has an auxiliary
device connected and is not
programmed to be.
Note: These codes do not affect
ABS performance and do not
illuminate the tractor trailer ABS
warning lamps.
X
X
X
X
X
X