GMC 4000 Series Service Manual page 534

cable from battery before removing instrument
cluster to prevent accidental grounding at ammeter.
1. Disconnect multiple wiring connector plug
from under dash.
2. Remove six screw s which attach instrument
cluster to dash panel and tilt cluster outward far
enough to gain access to connections at back of
gauges and units.
NOTE: It may be necessary to disconnect the
oil pressure gauge line before tilting the cluster
outward.
3. Disconnect drive cables, lines, and wiring
connections from each gauge and unit.
4. Each gauge and unit is retained in the clus­
ter by two mounting brackets. To remove a gauge
or unit, disconnect wiring, then remove nuts and
washers from gauge mounting bracket.
1 Voltmeter
2 Air pressure
3 Speedometer
4 Tachometer
5 Four Gauge Cluster
5a Oil Pressure Gauge
G M C S E R V I C E M A N U A L
5b Engine Temperature Gauge
5c Ammeter
5d Fuel Gauge
6 L.H. Turn Signal Tell-tale
7 Differential Lock Tell-tale
Figure 8 — Typical Instrum ent Cluster IC onven tion al C ab M o d e l)
CHASSIS ELECTRICAL AN D INSTRUMENTS
INSTALLATION
1. Position each gauge or unit in cluster and
install nuts and washers to secure to mounting
bracket.
2. Position instrument cluster in dash panel
far enough to gain access to rear of each gauge
and unit.
3. Connect drive cable, lines, and wiring con­
nectors to each gauge or unit. Insert tell-tale and
illumination lamp bulbs in sockets.
4. Move instrument cluster into position and
secure with retaining screw s. Connect multiple
plug connector under dash, then connect battery
cable to battery.
COWL ,"S" A N D "P" MODELS
The cluster contains a generator ammeter,
engine temperature gauge, oil pressure gauge, and
8 Low Oil Tell-tale
9 Water Temp. Tell-tale
10 Low Air Tell-tale
11 R.H. Turn Signal Tell-tale
12 Wiring Connector
Sec. 12
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