S15/T15 2WD Jimmy V6-262 4.3L (1991)
Blower Motor: Description and Operation
With A/C
CIRCUIT OPERATION
BLOWER CONTROLS
In all blower speeds except HI. the HTR-A/C Fuse supplies current to the Blower Motor. In high speed operation, current from the Blower Switch
energizes the High Blower Relay, permitting current to flow from the Battery Junction Block to the Blower Motor.
BLOWER LOW SPEED OPERATION
The Blower Motor only operates in Low Speed through the A/C-Heater Selector Switch. With the A/C-Heater Selector Switch in MAX A/C, NORM
A/C, BI-LEVEL, VENT, HEAT, or DEFROST, power through the A/C-Heater Selector Switch is available to the Blower Resistors through the
BRN/WHT (64) wire. The current then flows through all three resistors and the normally closed contacts of the High Blower Relay to the Blower Motor
and the Blower Motor runs at Low speed.
BLOWER MEDIUM LOW SPEED
OPERATION
With the Blower Switch in M1, current flows from the HTR-A/C-Fuse, through the A/C-Heater Selector Switch, the BRN/WHT (64) wire and the
Blower Switch to the TAN (63) wire at the Blower Resistors. Current then flows through two of the resistors and the normally closed contacts of the
High Blower Relay to the Blower Motor. The Blower Motor then runs at Medium Low speed.
BLOWER MEDIUM HIGH SPEED
OPERATION
With the Blower Switch in M2, the blower operates the same as in the Medium Low speed, except that the current is directed to the Blower Resistors
through the LT BLU (72) wire. Current passes through only one resistor. The Blower Motor then runs at Medium High speed.
BLOWER HIGH SPEED OPERATION
With the Blower Switch in HI, current bypasses the Blower Resistors and flows to the High Blower Relay through the ORN (52) wire. This current
energizes the relay and closes the normally open contacts of the relay. Current then flows from the Battery Junction Block, through the relay to the
Blower Motor, and the Blower Motor runs at High speed.