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Control Units

CONTROL UNITS LOCATION

Component Location
Audio Alarm Module On bracket, to left of steering column.
Cruise Control Module On brake pedal bracket.
Electronic Control Module (ECM)
4.3L Under driver's seat. See Figure.
5.0L & 5.7L - 1989 Under driver's seat. See Figure.
5.0L & 5.7L - 1990 Under driver's seat. See Figure.
7.4L - 1989 Under driver's seat. See Figure.
7.4L - 1990 Under driver's seat. See Figure.
Elect. Spark Control (ESC) Module
4.3L Under driver's seat. See Figure.
5.0L & 5.7L - 1989 Under driver's seat. See Figure.
5.0L & 5.7L - 1990 Under driver's seat. See Figure.
Glow Plug Controller (Diesel)
Diesel Component View On left rear of intake manifold. See Figure.
Diesel Engine Component View On left rear of intake manifold. See Figure.
Hot Fuel Handling Module
5.0L & 5.7L - 1989 Under driver's seat. See Figure.
5.0L & 5.7L - 1990 Under driver's seat. See Figure.
7.4L - 1989 Under driver's seat. See Figure.
7.4L - 1990 Under driver's seat. See Figure.
Hydro-Boost Elect. Delay Module Behind left side of instrument panel.
Light Driver Module (Diesel) Under right side of dash.
Power Door Lock Delay Module Above left kick panel.
Pulse Wiper Control Module Taped to harness, at right side of steering column.
RWAL Elect. Control Unit In engine compartment on bracket attached to master cylinder.