TM 5-2420-230-24-1
It allows the vehicle to be operated in a certain (hardwired) gear position.
Direction selection is accomplished with a separate 3 position electrical switch.
Use of this system allows to still move the vehicle in case of an EGS breakdown.
The override system is in fact a switch, which either connects the solenoid valves to the EGS or to the
'fixed gear' alternate direction switch.
In the first case the transmission is controlled electronically by the EGS, in the latter it is operated
manually in a preset gear.
Note :
When the override system is activated, all drivetrain protections are bypassed.
Using the override system can be of help to find out whether a problem is related to the
EGS OR if it is hydraulical, electromechanical, pneumatic.
7. SELFTEST FUNCTIONS
The EGS has special circuitry to help verifying its operation.
Three selftest modes are built into the EGS control programs :
Input test
Speed sensor test + Lamptest
Output test
The EGS furthermore has the ability to check for possible problems while driving (ON LINE
diagnostics).
As described in 4.4.2, the 'T' LED is used for identifying different Trouble(Shoot) modes. This is done
in combination with the status of the 'N' LED.
7.1 Operation of the 'N' and 'T' LED's
7.1.1 Overview
In normal situations (driving, no problems)
'T' LED is always OFF
When error is detected
'T' LED is ON or BLINKING
In selftest mode
'T' LED is always ON
7.1.2 Detailed operation
Situation
'N' LED
'T' LED
Normal Operation
On when transmission neutral
OFF
INTERNAL FAULT
ON
blinking SLOWLY
INPUT TEST
blinking SLOWLY
ON
OUTPUT TEST
blinking FAST
ON
SPEED SENSOR TEST
OFF
ON
EGS user manual. Page 20 of 25
SPICER CLARK-HURTH
Document reference : egsman4.doc
Revision date: 07/04/97
Ten Briele 3, 8200 Brugge, Belgium
Tel: +32/50/402445
Fax: +32/50/402402
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