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Doc. No. Y250910 (EN - Rev. 001)
September 2016
KB4TA / KB4TA D System Diagnostics
P r o d u c t D a t a
PD-203-390
Chart 3
Troubleshooting the Trailer-mounted ABS Warning Lamp Circuitry
KB4TA Module - X1 Wiring Harness
(Pin 1 - ABS Warning Lamp)
ISO1185-connector
(Pin 1 - ground / Pin 4 - stop lamp power)
12 11 10
9
8
7
Ground
Power
Trailer-mounted ABS warning
lamp did not illuminate during
the power-up sequence.
Troubleshoot the power supply to the
module.
Go to Chart 4.
Verify stop lamp supply at the
ISO 1185 connector.
Verify configuration and correct installati-
on of the trailer-mounted
warning lamp.
Continue if power (ISO1185 - pin 4) and
ground (ISO1185 - pin 1) wiring are OK.
Turn off the power to the module.
Inspect the condition of the ABS warning
lamp, connector and ground.
Using a volt/ohm meter, verify continuity
across the bulb. Verify continuity from
the ISO 1185 ground (pin 1) to the ABS
warning lamp ground pin.
If corrections are made, rerun the
power-up sequence.
Continue if the warning lamp and ground
wire check out OK.
With power off to the module, discon-
nect the 12-pin ECU connector.
Verify continuity from external ABS
WL pin (pin 1) of the ECU connector
and the ABS indicator lamp connec-
tor.
If corrections are made, rerun the
power-up sequence.
Trailer-mounted ABS warning
lamp remains “ON” during the
power-up sequence.
Determine if a module Diagnostic
Trouble Code (DTC) exists using
any of the following methods:
- KB4TA Blink Code Diagnostic.
Got to Quick Reference table.
- PC-diagnostic tool ECU
talk
®
If DTC(s) exist and corrections are
made, rerun the power-up sequence.
Continue if no DTCs are found and
the ABS module appears to be func-
tioning normally.
With power off to the module,
disconnect the 12-pin ECU con-
nector.
Using a volt meter, verify that the-
re is no a short to Vbat between
the external ABS WL pin (pin 1) of
the ECU connector and the ABS
warning lamp connector.
If corrections are made, rerun the
power-up sequence.
KB4TA D Module - X1 Wiring Harness
(Pin 8 - ABS Warning Lamp)
12 11 10
9
8
7
Y026787: 006: EN: Released: Fri Nov 11 11:18:50 CET 2016:
