Mechanics

BLOWER MOTOR

1996 Honda Passport

Heater problem
1996 Honda Passport 6 cyl Four Wheel Drive Automatic 140000 miles

I have no power coming to my 20 amp fuse under the hood for my blower motor. I checked both sides of the fuse and tried new fuses. I also tried a different relay for the blower relay under the hood. So no power at the blower motor or the resistor. The blower motor was tested with 12 volts and is good.
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Merlin1052
January 22, 2010.



Hi merlin1052,

Thank you for the donation.

Unplug the relay and test for power supply to the # 3 terminal ( White/Red wire) If power is not available, check the 60 A main fuse.

If power is available, use a jumper across terminal #3 and #4 of relay socket and test the fuse for battery voltage. If voltage is present, either thr relay or its coil circuit is bad.

Terminal # 2 is grounded, test the grond connection.

Terminal # 1 receives power from the alternator to activate the heater relay when ignition switch is turned ON.

KHLow2008
Jan 22, 2010.
I tried everything you said. The relay has power and ground. I swapped out the relay with one I know was good and still nothing. The 60 amp fuse is good. I forgot to mention that when the blower first went out I noticed the previous owner had a 25 amp fuse instead of a 20 amp fuse in the fuse box under the hood for the heater. It has a 20 in it now. Could the blower motor switch (HVAC control switch) cause there to be no power to the motor. In the manual it shows a thermo fuse between the blower motor switch and the resistor, but I can't find it. Do you know where it is supposed to be on this car and if that could cause this? When you said the coil circuit, what are you refering to? If it is the wiring, instead of trying to find the bad wire. Is there a way that I can wire it up myself. If so, can you tell me how.
Sorry for all the questions and thank you very much for your time.
Nick

Tiny
Merlin1052
Jan 22, 2010.
If you do not have voltage at the 20 A fuse, it is not a fault with the resistor or blower switch.

If you apply battery voltage to the 20 A fuse, does the fan blower works? If yes, you need to check the power supply between the heater relay and the fuse.

Did you jump the teminals to see if power is available at the fuse?

KHLow2008
Jan 23, 2010.
Sorry, I am just an average home mechanic at best. So to apply power to the 20 amp fuse, do I pull out the fuse and run a wire (jumper) to the terminals from the battery or any 12 volt source? The power supply between the relay and fuse is just a wire, right? I used the test light to check for power at the fuse. Thats basically the same thing right?
Thanks again!
Nick

Tiny
Merlin1052
Jan 23, 2010.
I applied 12 volts to the 20 amp heater fuse and nothing happened. If the relay has power can I just run a wire from the relay to the blower motor and put an inline fuse in it.
Any more input would be much appreciated!
Thanks in advance!

Tiny
Merlin1052
Jan 23, 2010.
Sorry for the delay in replying. I was having difficulties logging onto the site.

You can just use a live wire to tap into the fuse without removing it.

If applying battery voltage to the 20 A fuse did not help, then there must be something wrong with the wire between the fuse and the blower motor or blower motor, resistor and/or switch.

At blower motor there is a 2 pin connector, if power is applied to the 20 A fuse, check if voltage is present at one of the wires.

If voltage is abvailable and you are not able to operate the blower motor, then it is a fault with the blower motor or resistor or the control switch.

KHLow2008
Jan 25, 2010.
I am about ready to take it to the shop, but I would rather not because I will be trading it in soon anyway. I have tried everything you said to try and still no power to the fuse or blower motor. Can you please tell me away to wire this up that is not to dangerous. Maybe tapping into another fuse or something. Wiring diagram in my manual is hard to make sense out of.

Thank for all your help!

Tiny
Merlin1052
Jan 25, 2010.
Here is a wiring schematic of the heater blower.

The easiest way is to apply voltage to the blower motor Blue/White wire through a fused source.

With voltage applied to the 20 A fuse, are you getting voltage at the Blue/White wire? If yes, th most likely problem would be a fault with the relay circuit. It gets is coil power source from the voltage regulator. You can try disconnecting the power source from the alternatos and rewire it to the ignition switch or ACC wire circuit.


http://www.2carpros.com/forum/automotive_pictures/192750_HeaterCircuit96Passport6cylFig05_1.jpg


KHLow2008
Jan 25, 2010.
Sorry I was not more specific. I applied 12v to the 20 amp fuse and had no power at the blue/white wire at the blower motor. Is the blue/white wire the power source going to the alternator? So just take the wire and run it to the ignition switch or ACC circuit?

Tiny
Merlin1052
Jan 25, 2010.
The Blue/White wire is connected to the fuse. I believe this wire is broken in between. Alternator wire is for activating the relay which is not the problem, it seems.

You can use it to connect to ACC with a fuse in between.

KHLow2008
Jan 25, 2010.