1320whtrex

I recently had a problem where my blower wasn't working. Turned out my problem was that someone removed my 40A fuse(to test on another car) and replaced it in the wrong section when it was put back in. However the problem I am seeing now that I am having is that the blower blows(on high) once I turn the key on. Switched on or off.... Never had I setup a constant power wire connection to the blower, other than to just check and make sure that the blower works when I was having my previous problem. Anyone ever experienced something like this before?

Former User

Does unplugging the blower motor relay in the hood fuse box prevent the blower from running?

1320whtrex

Yes... If I unplug the blower motor relay or the blower motor fuse in the hood fuse box, the blower will not work.. If I unplug the blower motor resistor, then the AC will not work on anything but high. But once I plug it back in, it blows constantly.

Former User

-Does unplugging the power transistor prevent the blower from running?

-Does unplugging the heater control panel prevent the blower from running?

1320whtrex

Power Transistor? If you are referring to the Blower Motor Resistor behind the glove box, then the answer is:
-If the AC is on high, no
-If the AC is on anything lower than high, yes.
No.

Former User

I missed this. So unplugging the power transistor restores control to the fan switch? In other words, the fan switch will turn the blower on and off when the power transistor is unplugged?

1320whtrex

Oh okay... Unplugging the power transistor will only turn it off if it's on a setting less than high, otherwise, there is no control and it just blows air(COLD air if the AC Button is on)

Former User

The 96-98 Civic climate control uses a resistor whereas the 99-00 Civic climate control uses a power transistor. I think you mentioned in another thread that you have a 99-00 Civic climate control. Is this correct?

1320whtrex

Correct... The car is a 96 but I converted the entire behind the dash AC system to 99-00...

Former User

Am I understanding your information correctly?

1) Unplugging the power transistor does NOT stop the blower from running, IF the heater control panel is set to OFF or HIGH, right? It does turn the blower off when the heater control panel is set anywhere between OFF and HIGH, right?

2) Unplugging the connectors at the rear of heater control panel does NOT prevent the blower from running, right?

1320whtrex

No.... It only stops the blower from running if it is set to anything but high.. If it is on high, then it will work if the blower is work if the transistor is plugged in or not.

Correct......

Former User

Sorry, I'm confused by the wording here.

And are you saying that with the transistor unplugged, the blower motor stops running when the heater control panel dial is set to the off position?

If this^ is correct, I think the power transistor may be bad. It can be tested.

1320whtrex

Sorry.. It was suppose to say
"No.... It only stops the blower from running if it is set to anything but high.. If it is on high, then it will work if the transistor is plugged in or not."

Hope that makes much better sense.

Former User

Do I now have it right?

1) Key on; transistor and heater control panel plugged in:
Blower runs on high regardless of the switch position.

2) Key on; transistor unplugged; heater control panel plugged in:
Blower runs on high when switch is set on high. Blower does not run when switch is set to other positions.

3) Key on; transistor plugged in; heater control panel unplugged:
Blower runs on high.

1320whtrex

1. Yes
2. Yes
3. Yes

Former User

Test the power transistor:

1320whtrex

Sorry I haven't had a chance to update... I replaced the power transistor and it works fine now... I guess it can go bad two ways.. Thanks alot for the help...