LeeBoy 8520C - ECU Powering Up Check; Power Distribution Box (PDB) Overview

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LeeBoy 8520C Conveyor Paver 5-65
Maintenance
Check ECU Powering UpCheck ECU Powering Up
Relays
7A 30
SCR HT RLY Coil + ACU Main PWR
8A 20
Main RLY PWR
9A 5
ECU RLY Coil +
10A 5
ECU RLY PWR
10E 30
B+ to Key 30 PWR
9E
5
Main RLY PWR
8E 5
Main RLY Coil +
7E 30
Main RLY PWR
10C 10
Nox/DEF Sensors PWR
9C
Start ECU + RLY Coil
5
Fuses
Figure 5-73. Power Distribution Box (PDB)
Each engine has a power distribution block (PDB) on the main
engine harness that provides power to the ECU through the ECU
control relay, main relay and fuses. (Figure 5-73)
To check the ECU powering up:
1. Locate the PDB on the right side of the paver inside
the engine access door.
2. Fuses can be checked by removing the fuse and
using a continuity tester OR checking for +12VDC on
each pin on the back of the fuse.
3. Conrm operation of ECU and main relays:
• If the ECU relay is not energizing, starter will not
operate.
• If the main relay is not energizing, the fuel pump
will not operate.
If none of these procedures correct the problem, con-
tact your authorized LeeBoy dealer for assistance.