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Control Units

CONTROL UNITS LOCATION

Component Location
ABS Control Module On left side of engine compartment.
Audio Alarm Module Behind dash, below fuse block.
Cruise Control Module Behind instrument panel, near steering column.
Digital Ratio Adaptor Controller (DRAC) On parking brake lever assembly.
Electronic Control Module (ECM)
4.3L VIN Z Under driver's seat. See Figure.
5.0L VIN H & 5.7L VIN K Under driver's seat. See Figure.
7.4L VIN N Under driver's seat. See Figure.
Elec. Spark Control (ESC) Module
4.3L VIN Z Under driver's seat. See Figure.
5.0L VIN H & 5.7L VIN K Under driver's seat. See Figure.
7.4L VIN N Under driver's seat. See Figure.
Glow Plug Controller (Diesel)
Controls & Relays On left rear of intake manifold. See Figure.
6.2L Diesel On left rear of intake manifold. See Figure.
Hot Fuel Module
5.0L VIN H & 5.7L VIN K Under driver's seat. See Figure.
7.4L VIN N Under driver's seat. See Figure.
Hydro-Boost Elec. Delay Module Behind left side of instrument panel.
Light Driver Module (Diesel) Under right side of dash.
Power Door Lock Delay Module Behind dash, to right of steering column.
Pulse Wiper Control Module Taped to harness, at left side of steering column.