User's Manual
11
FRT Red LED
MID Red LED (See Note)
RER Red LED
RHT Red LED
LFT Red LED
TRC Red LED
MOD Red LED
SEN Red LED
ECU Red LED
VLT Green LED
RESET + No LED
Note: The MID LED is used with some but not all vehicles.
When six speed sensors are not installed this LED
is not used in the diagnostic process. However, it
will light when a magnet is placed on the RESET
switch in the diagnostic display.
“FRT” (Front) LED
This Red LED illuminates and latches ON in order to
indicate the location of a problem component or its wiring.
It will light in conjunction with either the RIGHT or LEFT
LED and the MOD or SENS LED.
“MID” (Mid Axle) LED
This Red LED is not used in all installations. On those
vehicles that have six speed sensors installed, this Red
LED illuminates and latches ON to indicate the location
of a problem speed sensor or its wiring. The “MID” LED
should not illuminate with the “MOD” LED.
“RER” (Rear) LED
This Red LED illuminates and latches ON in order to
indicate the location of a problem component or its wiring.
It will light in conjunction with either the RIGHT or LEFT
LED and the MOD or SENS LED
“RHT” (Right) LED
This Red LED illuminates and latches ON in order to
indicate the location of a problem component or its wiring.
It will light in conjunction with either the FRONT or REAR
LED and the MOD or SENS LED.
“LFT” (Left) LED
This Red LED illuminates and latches ON in order to
indicate the location of a problem component or its wiring.
It will light in conjunction with either the FRONT or REAR
LED and the MOD or SENS LED.
“TRC” (Traction) LED
This Red LED illuminates and latches ON to indicate a
permanent problem in the traction control system. It may be
illuminated with the MOD LED or may illuminate by itself.
NOTE: If an intermittent problem exists with the wiring
to the engine control module (ECM), this LED will go on.
However, it will not latch—it will go out when the problem
“corrects” itself.
“MOD” (Modulator) LED
This Red LED illuminates and latches ON to indicate
a permanent or intermittent open or short circuit in the
solenoids of one of the four M-21
™
modulators or the wiring
connecting them to the system. When indicating a problem
with an M-21
™
modulator this LED will be illuminated with
two positioning LEDs (RHT/LFT + FRT/RER). NOTE: The
MID positioning LED should not be illuminated with this
LED. This LED is also used to indicate a problem with an
ATR-1
™
or ATR-2
™
, antilock traction relay, solenoid. When
illuminated for a traction system problem the TRC LED will
also be on.
“SEN” (Speed Sensor) LED
This Red LED illuminates and latches ON to indicate
permanent or intermittent failure. The failures indicated are;
open or shorted wheel does not conform to design criteria.
The “SEN” LED will be illuminated with two positioning
LEDs (RHT/LFT + FRT/MID/RER).
“ECU” (Electronic Control Unit) LED
This Red LED, when illuminated, indicates that the
controller itself has failed. It is latched ON for all EC-16
™
controller failures except low voltage. Before controller
replacement is considered, always check vehicle voltage
to the controller.
“VLT” LED
This Green LED illuminates and remains ON during vehicle
operation to indicate that vehicle power is reaching the
controller. If vehicle power is out of range (below 11 VDC
or above 17 VDC) this LED will fl ash until power is brought
into range.
“RESET”
Beneath the RESET area of the display is a magnetically
sensitive switch that is used to reset the diagnostic system.
The device will respond to a magnet which has strength
suffi cient to lift a three (3) ounce weight. Momentarily
holding a magnet against the RESET will cause ALL LEDs
to light during the time the magnet is against it. Holding
a magnet against the RESET longer than 20 seconds will
cause the newer version EC-16
™
controller to initiate the
self confi guration feature.
EC-16
™
CONTROLLER CONFIGURATION
GENERAL
All EC-16
™
controllers manufactured on or after August
1, 1995 incorporate the self confi guring feature. New,
replacement EC-16
™
controllers will be provided factory
preprogrammed for 6 speed sensor inputs and both the
differential braking and torque limiting features for traction
control.