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No blower motor function at any speed setting. When I hotwire the motor directly to power the motor blows fine. Thinking it's not resistors because doesn't work at any speed setting. Unplugged and re plugged switch, but I've read this switch going bad is uncommon. Everything else in the car seems to work fine. Checked fuses and relay, they seem to be fine. Any other thoughts before I tear the dash apart?
Re: 1997 Honda Civic no blower on any speed setting
The cause may be due to a faulty heater fan switch. But, tests are needed.
Try the following tests.
Note: Make sure you properly identify the correct wire terminals before beginning. On female connector, the wire numbering is from the wire side.
1. Locate Connector C723 behind the front console.
2. Unplug Connector C723 and leave it unplugged. With a small paper clip or wire, individual jump terminal no. 15 cavity (Blk wire) to the following terminals with the ignition switch in the ON position (car does not have to be running):
terminal no. 1 cavity (Blu/Wht wire) - Blue wire with white stripe.
terminal no. 2 cavity (Blu wire)
terminal no. 11 cavity (Blu/Yel wire)
terminal no. 16 cavity (Blu/Blk wire)
Note: Terminal no. 15 (blk wire) is ground. The test will individually provide ground to the above wires.
Terminal no. 1, 2, and 11 flow through the blower resistor; so, if the resistor is functioning properly, the blower fan show run but, at different speeds. Terminal no. 16 goes directly to the blower motor.
Report your findings. Do not replace anything yet.
Re: 1997 Honda Civic no blower on any speed setting
Power for the motor comes from a fuse and relay in the underhood fuse box. The relay pulls in whenever the key is on to supply the motor. The other lead of the motor is grounded through the switch and resistor.
Everything plugged in, turn the key on, turn the switch to high and measure the voltage from each of the two wires at the motor to ground.
12 volts on both wires -- problem in the ground side of the circuit (switch, resistor).
zero volts on both wires -- problem in the power side of the circuit (fuse, relay, fuse box)
12 volts on one wire, zero on the other -- motor has power, should be running, so bad motor.
Re: 1997 Honda Civic no blower on any speed setting
Originally Posted by tech8
The cause may be due to a faulty heater fan switch. But, tests are needed.
Try the following tests.
Note: Make sure you properly identify the correct wire terminals before beginning. On female connector, the wire numbering is from the wire side.
1. Locate Connector C723 behind the front console.
2. Unplug Connector C723 and leave it unplugged. With a small paper clip or wire, individual jump terminal no. 15 cavity (Blk wire) to the following terminals with the ignition switch in the ON position (car does not have to be running):
terminal no. 1 cavity (Blu/Wht wire) - Blue wire with white stripe.
terminal no. 2 cavity (Blu wire)
terminal no. 11 cavity (Blu/Yel wire)
terminal no. 16 cavity (Blu/Blk wire)
Note: Terminal no. 15 (blk wire) is ground. The test will individually provide ground to the above wires.
Terminal no. 1, 2, and 11 flow through the blower resistor; so, if the resistor is functioning properly, the blower fan show run but, at different speeds. Terminal no. 16 goes directly to the blower motor.
Report your findings. Do not replace anything yet.
No power to 1,2, or 11, what do I do next? What do I do to hot wire the blower motor to the battery? Everything I’ve tried hasn’t worked.
Re: 1997 Honda Civic no blower on any speed setting
Originally Posted by moparmadman
No power to 1,2, or 11, what do I do next?
Originally Posted by tech8
Note: Terminal no. 15 (blk wire) is ground. The test will individually provide ground to the above wires.
Terminal no. 1, 2, and 11 flow through the blower resistor; so, if the resistor is functioning properly, the blower fan show run but, at different speeds. Terminal no. 16 goes directly to the blower motor.
There shouldn't be power (+) at terminal 1, 2, or 11. Those are wires that suppose to flow ground (-) from terminal no. 15 through the blower resistor. My test was to jump a wire to terminal no. 1, 2, or 11 to essentially bypass the heater control switch and resistor to send the ground to the motor. Did you follow my test?
Re: 1997 Honda Civic no blower on any speed setting
Originally Posted by tech8
There shouldn't be power (+) at terminal 1, 2, or 11. Those are wires that suppose to flow ground (-) from terminal no. 15 through the blower resistor. My test was to jump a wire to terminal no. 1, 2, or 11 to essentially bypass the heater control switch and resistor to send the ground to the motor. Did you follow my test?
next question. How do I Hotwire the blower to test it?? Sorry I’m just not super good with wiring