User's Manual

14
TROUBLESHOOTING
IMPORTANT BEFORE TROUBLESHOOTING:
1. Determine if the vehicle is equipped with traction
control. The presence of a traction condition lamp on
the dash can be used.
2. Some vehicles are equipped with a traction control
“disabling switch.” If so equipped, ENABLE THE
TRACTION SYSTEM BEFORE BEGINNING THE
TROUBLESHOOTING.
3. If the vehicle is equipped with traction control and is a
tandem axle unit, note the number of drive axles. The
“MID” diagnostic LED is used only on 6x4 vehicles.
GENERAL
While the EC-16
controller diagnostic display locates
a speci c problem area, it is still necessary to con rm
whether the problem resides in the component itself or the
wiring. The following troubleshooting procedure is devoted
to narrowing the problem to either the wiring or a speci c
AntiLock or traction component. It should be noted that
ALL TROUBLESHOOTING BEGINS BY OBSERVING
THE ANTILOCK AND TRACTION CONDITION LAMPS
ON THE DASH. All troubleshooting should begin by rst
performing the “Initial Start Up Procedure” and following
the directions contained in it.
TROUBLESHOOTING TIPS
1. Begin by observing the dash condition lamp(s) and
performing the “Initial Start Up Procedure.”
2. The troubleshooting technician should record all
ndings and the action taken during the troubleshooting
process.
3. No voltage or resistance tests are performed into the
EC-16
controller. All voltage and resistance tests
are performed by beginning at the wire harness half
of the connector and moving AWAY from the EC-16
controller toward an antilock traction system component
(modulator, wheel speed sensor, etc.)
4. If a problem mysteriously reoccurs and no apparent
cause can be detected during troubleshooting, closely
inspect the quality of the power supply to the antilock
system. Check the vehicle wiring, wiring connectors
AND the alternator. Defects in these components can
cause false failure indications.