G 2500 3/4 Ton Van V6-262 4.3L VIN Z TBI (1995)
Blower Motor: Initial Inspection and Diagnostic Overview
Troubleshooting Hints
Check condition of HTR A/C Fuse. If fuse is blown, locate and repair source of overload. Replace fuse.
Circuit Operation
The Blower Motor delivers air to the interior of the vehicle. Its speed is controlled by the Blower Switch and the Blower Resistor. When the Ignition
Switch is in RUN, battery voltage is supplied to the Blower Switch. With the Blower Switch in LO, voltage is supplied across all three Blower Resistors
through the high blower relay to the Blower Motor. The Blower Motor runs at its slowest speed.
With the Blower Switch in MED1, one of the Blower Resistors is bypassed and the Blower Motor runs faster. With the Blower Switch in MED2, two
Blower Resistors are bypassed and the Blower Motor runs faster. When the Blower Switch is set to HI, battery voltage is supplied directly to the Blower
Motor through the high blower relay and the Blower Motor runs at its fastest speed.
Troubleshooting Hints
Check condition of AUX HTR A/C Fuse. If fuse is blown, locate and repair source of overload. Replace fuse.
Circuit Operation
The Blower Motor delivers air to the rear interior of the vehicle. Its speed is controlled by the Blower Switch and the Blower Resistors. Note that the
Blower Switch provides ground to the Blower Resistors rather than battery voltage as in most common systems. When the Ignition Switch is in RUN,
battery voltage is supplied to the Blower Motor. With the Blower Switch in LO, voltage is supplied across both Blower Resistors and the Blower Motor.
The Blower Motor runs at its slowest speed. With the Blower Switch in MED, one of the Blower Resistors is bypassed and the Blower Motor runs faster.
When the Blower Switch is set to HI, direct ground is provided to the Blower Motor and the Blower Motor runs at its fastest speed.
Troubleshooting Hints
Check condition of HTR A/C Fuse. If fuse is blown, locate and repair source of overload. Replace fuse.
Circuit Operation
The Blower Motor delivers air to the interior of the vehicle. Its speed is controlled by the Blower Switch and the Blower Resistor. When the Ignition
Switch is in RUN, battery voltage is supplied to the Blower Switch. With the Blower Switch in LO, voltage is supplied across both Blower Resistors and
the Blower Motor. The Blower Motor runs at its slowest speed.
With the Blower Switch in MED, one of the Blower Resistors is bypassed and the Blower Motor runs faster. When the Blower Switch is set to HI,
battery voltage is supplied directly to the Blower Motor and the Blower Motor runs at its fastest speed.
Troubleshooting Hints
Before proceeding to the system diagnosis perform the following visual inspections.
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Check to see that AUX HTR A/C Fuse is not blown. If fuse is blown, locate and repair source of overload.
Circuit Operation
The Auxiliary A/C Blower Motor Delivers air to the interior of the vehicle. Its speed is controlled by the Blower Switch and the Blower Resistors. When
the Ignition Switch is in RUN, battery voltage is supplied to the Blower Switch. With the Blower Switch in LO, voltage is applied across both Blower
Resistors and the Blower Motor. The Blower Motor runs at its slowest speed. With the Blower Switch in MED one of the Blower Resistors is bypassed
and the Blower Motor run faster. When the Blower Switch is set to HI, battery voltage is supplied directly to the Blower Motor and the Blower Motor
runs at its fastest speed.
