Chrysler DODGE D150 1993 Service Manual page 874

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FUEL SYSTEM 14 - 55
Fig. 30 Dual Oxygen Sensors—5.9L HDC Engine
IDLE AIR CONTROL (IAC) MOTOR TEST
To perform a complete test of IAC motor (Fig. 81)
and its circuitry, refer to DRB II scan tool and appro­
priate Powertrain Diagnostics Procedures manual. To
test the IAC motor only, special IAC motor exerciser
tool number 7558 (Fig. 32) may be used.
C A U T I O N : Proper safety p r e c a u t i o n s must be taken
when testing the I A C motor,
• Set the parking brake and block the drive wheels
• Route all tester cables away from the cooling fans,
drive belt, pulleys and exhaust components
• Provide proper ventilation while operating the en­
gine
• Always return the engine idle speed to normal be­
fore disconnecting the exerciser tool
(1) With the ignition OFF, disconnect the IAC mo­
tor wire connector at throttle body (Fig. 31).
(2) Plug the exerciser tool (7558) harness connector
into the IAC motor (Fig. 32).
MANIFOLD ABSOLUTE
Fig. 31 IAC Motor—Typical
Fig. 32 IAC Motor Testing— Typical
(3) Connect the red clip of exerciser tool (7558) to
battery positive terminal. Connect the black clip to
negative battery terminal. The red light on the exer­
ciser tool will be illuminated when the exerciser is
properly connected to battery.
(4) Start engine.
When the switch is in the HIGH or LOW position,
the light on the exerciser tool will flash. This indi­
cates t h a t voltage pulses are being sent to the IAC
stepper motor.