Spicer TPCS Troubleshooting Guide - Manual (Page 16)

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Diagnostics
Diagnostics
This section covers the equipment and procedures used to
find and correct Tire Pressure Control System problems.
Test Equipment
Tire Pressure Control System troubleshooting can be
performed at three levels:
1. PC diagnostics.
2. Handheld tester.
3. Operator Control Panel service codes (if vehicle is
equipped with an OCP).
Regardless of the testing equipment used, the troubleshoot-
ing procedures will be based upon the diagnostic service
codes. Diagnostic tools offer the advantages of computer-
aided testing without interpreting service codes.
Tire Pressure Control System Diagnostics
The onboard system diagnostics are an important feature of
Spicer’s Tire Pressure Control System. This section describes
the use of service codes to identify Tire Pressure Control
System operating problems.
The Tire Pressure Control System uses a code to identify ser-
vice issues. The codes can be extracted from the ECU mem-
ory using a diagnostic service tool equipped with the
appropriate software. In addition, systems equipped with an
Operator Control Panel (OCP) will report codes directly on the
display. Refer to the service code chart for more detailed
information on service codes.
Historical Service Codes
Any time a fault occurs the system will log a fault in memory
of the ECU. If the system becomes inoperative, the Driver Dis-
play Module (DDM) will report two dashes (- -) or an actual
service code will be displayed on the Operator Control Panel.
(Only the most recent code is displayed by the
Operator Control Panel). Historical codes are stored in
memory. Historical codes can only be accessed by a
diagnostic tool. Historical codes are automatically cleared
after 50 ECU resets with no active faults.
Service Codes
The Service Codes are described in the Troubleshooting
section. Some service codes also identify the component that
is associated with the problem. A list of possible causes is
shown in order of most likely occurrence.
Test Modes
Diagnostic tools allow the system to be placed in several
diagnostic modes:
Info - Display ECU information and configuration.
Codes - Active and historic codes are listed as reported by the
ECU.
Monitor (Normal) - TPCS operates normally, while status of
system components is observed.
Test - The following operations can be performed on each
channel (axle group):
• Check & Hold - System checks and
displays the pressures, then holds pressure in air
lines (quick test of control line and seal integrity).
• Deflate - System "manually" deflates (test the
deflation signal).
• Inflate - System "manually" inflates (test for large
leaks).
• Hold - Pressure is held in control lines (test for small
leaks).
Setup - Allows the technician to modify parameters such as
target tire pressures, etc.