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(CU) of ABS (in cabin at the right under the instrument panel), ABS diag
nostic button (in the middle of the instrument panel), ABS failure warning
lamp (on the right in the instrument cluster) and ABS harness connecting sen
sors and input choppers with ABS CU.
Two supply circuits are connected to ABS CU: for input choppers via 1st
25A fuse in the upper fuse block and direct for ABS CU via 11th 5A fuse in the
upper fuse block.
The instrument cluster is provided with the warning lamp. It lights up for
several seconds each time the engine control switch is turned on and then goes
out. It evidences that ABS system circuits connected to ABS CU are in sound
condition. If the warning lamp lights continuously or it lights up during vehi
cle movement it indicates that ABS circuits went out of order (but service brake
system maintains serviceability as if without ABS). ABS failure warning lamp
is also lights up automatically at constrained disconnection of supply socket
from ABS control unit.
When ABS failure is confirmed the troubleshooting should be carried out
at service station.
ABS electrical diagram is shown in Fig. 8.6.
Pin
Circuit
ABS CU supply
Input chopper supply
ABS CU common
Input choppers common
Pilot lamp
Pin
D7 - control unit
887 - front, left speed sensor
Y56 - front, left input chopper
888 - front, right speed sensor
Y57 - rear, left input chopper
889 - rear, left speed sensor
890 - rear right speed sensor
Y58 - rear, right input chopper
X1 - 18 pin connector
X2 - 6 pin connector
X3 - 9 pin connector
X4 - 15 pin connector
Fig. 8.6. ABS System Electric Circuit Diagram
See vehicle electrical equipment diagram
1)
Pin
Pin
