Fan For Heater Does Not Work On 4.1

[Maigaard]

I have a 1996 4.1.

A few months back, the lights for the heating controls as well as the fan starting working just sometimes. Now, it totally stopped working (no lights, and the fan does not work regardless of setting). The heating system works - so when the car is in motion, heat does come through the vents - though without the fan, it's certainly not a lot of airflow...

I checked the fuses I could find (engine compartment, left and right front seat leg room), and they seem to be OK.

Anyone has experience in where the electrical problem most likely is to be found?

Everything else works (radio, rest of dashboard lighting, clock, instruments etc).

/Soren

[bothwell_buyer]

I have a 1996 4.1.

A few months back, the lights for the heating controls as well as the fan starting working just sometimes. Now, it totally stopped working (no lights, and the fan does not work regardless of setting). The heating system works - so when the car is in motion, heat does come through the vents - though without the fan, it's certainly not a lot of airflow...

I checked the fuses I could find (engine compartment, left and right front seat leg room), and they seem to be OK.

Anyone has experience in where the electrical problem most likely is to be found?

Everything else works (radio, rest of dashboard lighting, clock, instruments etc).

/Soren

Hello and welcome to the forum!

First, you are lucky the clock works!! These usually stopped working after just a few years....it was caused by a loose connection on the clocks circuit board. A thump on the dashboard often brought it back on.

The dashboard lights don't last forever - I'm down to a light at the speedo/fuel guage, and 1 other on the dash. Those around the heater controls stopped working years ago and the light around the rpm stopped a few weeks ago. Its a fairly simple job to take the dashboard off and then to replace the bulbs. Just need to watch that you disconnect the Battery to dis-arm the airbag (assuming you have an electrically activated one which is probable).

If the fan does not work at all, then you can get to it whulst you have the dashboard out......try putting 12volts across the fan - if it doesn't work its plain worn out and you can try getting a 2nd hand one from a breaker.

[Maigaard]

I have a 1996 4.1.

A few months back, the lights for the heating controls as well as the fan starting working just sometimes. Now, it totally stopped working (no lights, and the fan does not work regardless of setting). The heating system works - so when the car is in motion, heat does come through the vents - though without the fan, it's certainly not a lot of airflow...

I checked the fuses I could find (engine compartment, left and right front seat leg room), and they seem to be OK.

Anyone has experience in where the electrical problem most likely is to be found?

Everything else works (radio, rest of dashboard lighting, clock, instruments etc).

/Soren

Hello and welcome to the forum!

First, you are lucky the clock works!! These usually stopped working after just a few years....it was caused by a loose connection on the clocks circuit board. A thump on the dashboard often brought it back on.

The dashboard lights don't last forever - I'm down to a light at the speedo/fuel guage, and 1 other on the dash. Those around the heater controls stopped working years ago and the light around the rpm stopped a few weeks ago. Its a fairly simple job to take the dashboard off and then to replace the bulbs. Just need to watch that you disconnect the Battery to dis-arm the airbag (assuming you have an electrically activated one which is probable).

If the fan does not work at all, then you can get to it whulst you have the dashboard out......try putting 12volts across the fan - if it doesn't work its plain worn out and you can try getting a 2nd hand one from a breaker.

Hi.

Thanks for your reply!

I just found it odd that the lights and the fan would stop working at the same time which to me indicated a more generic electrical problem than just the fan itself.

I have tried going through the 5 fuse compartments, but I can't see a single fuse that is labeled "fan" or similar. And the owners manual does not show which fuses are found where...

Do you by any chance know which one I should check again?

If I do remove the dashboard, do you mean that I try to put 12V over the fan directly from the Battery, or just using the connector already there?

Also, the car has an alarm / immobilizer. I have no idea how it works, but I assume that disconnecting the Battery would trigger this. Can I remove the dashboard without disconnecting the battery somehow?

Thanks!

/Soren

[bothwell_buyer]

Hi.

Thanks for your reply!

I just found it odd that the lights and the fan would stop working at the same time which to me indicated a more generic electrical problem than just the fan itself.

I have tried going through the 5 fuse compartments, but I can't see a single fuse that is labeled "fan" or similar. And the owners manual does not show which fuses are found where...

Do you by any chance know which one I should check again?

If I do remove the dashboard, do you mean that I try to put 12V over the fan directly from the Battery, or just using the connector already there?

Also, the car has an alarm / immobilizer. I have no idea how it works, but I assume that disconnecting the Battery would trigger this. Can I remove the dashboard without disconnecting the Battery somehow?

Thanks!

/Soren

ok

Lets have a look at this - on one of my wiring diagrams it shows the fan/blower on the same circuit as the lights.

From the battery, it goes to a 100Amp fuse in the fuse block. From there it gets to the 15A tail-light fuse ....can't remember where that is - under bonnet?

Now thinking about it, the panel lights come on when the lights are put on so something makes sense......

Next it goes to a taillight relay - again I think thats up front somewhere? Assuming your taqillights work ok, then items up to now must be working.

From there, the supply splits up into various wires going to lights etc.

NOW - the supply goes through the various lights and fan switch......then finds ground (earth).... whilst the panel lights will go through the rheostat (panel light dimmer) before going to earth.

So, after thinking about this one, I would use a multimeter to measure resistance from the earth side of the fan to the earth terminal of the battery, or a known good earthing point. As you say that the lot went out at one time, then I think it points to a faulty earth somewhere.

You can try checking the fuse box in the passenger (well in the UK it is) footwell to look for signs of corrosion or loose terminals on the earth - its a favourite spot as it often gets affected by incoming damp.

To try to find where the earth connects behind the dash would be a longer job.....so I'd even try fixing a temporary earth onto the earth side of the fan connection. The fan is more accessible by removing the plastic panels from below the dash..... check which wire is the 12v supply and which is thus earth. If the earth connection has gone faulty, you could try running an earth from the earth at the fan.

There are a couple of short posts on the rav4wrld forum suggesting the fuses are in the footwell - below the steering wheel on left hand drive cars.

Have a try at that, before removing dash. Let me know .

[Maigaard]

ok

Lets have a look at this - on one of my wiring diagrams it shows the fan/blower on the same circuit as the lights.

From the battery, it goes to a 100Amp fuse in the fuse block. From there it gets to the 15A tail-light fuse ....can't remember where that is - under bonnet?

Now thinking about it, the panel lights come on when the lights are put on so something makes sense......

Next it goes to a taillight relay - again I think thats up front somewhere? Assuming your taqillights work ok, then items up to now must be working.

From there, the supply splits up into various wires going to lights etc.

NOW - the supply goes through the various lights and fan switch......then finds ground (earth).... whilst the panel lights will go through the rheostat (panel light dimmer) before going to earth.

So, after thinking about this one, I would use a multimeter to measure resistance from the earth side of the fan to the earth terminal of the battery, or a known good earthing point. As you say that the lot went out at one time, then I think it points to a faulty earth somewhere.

You can try checking the fuse box in the passenger (well in the UK it is) footwell to look for signs of corrosion or loose terminals on the earth - its a favourite spot as it often gets affected by incoming damp.

To try to find where the earth connects behind the dash would be a longer job.....so I'd even try fixing a temporary earth onto the earth side of the fan connection. The fan is more accessible by removing the plastic panels from below the dash..... check which wire is the 12v supply and which is thus earth. If the earth connection has gone faulty, you could try running an earth from the earth at the fan.

There are a couple of short posts on the rav4wrld forum suggesting the fuses are in the footwell - below the steering wheel on left hand drive cars.

Have a try at that, before removing dash. Let me know .

I finally got around to taking a look at the blower.

I took the part of the dash apart that is easily accessible by removing the glove compartment and the side trimmings on the passenger side.

This way, I could check the relay and the connection to the blower.

Now, the relay works in the sense that it "clicks" when I switch the fan switch on (any speed).

The connector to the blower receives 0V when the switch is off, and receives 2V when the switch is on regardless of speed. Odd.

The ground is 25 ohms off from true ground.

Anyway, I then placed 12V directly onto the blower. It still does not run.

So, I figure that the blower itself is no longer with us and needs a proper funeral.

I'll see if I can find a used one somewhere. Anyone knows how to take it out without removing the entire dash board?

But even so, I assume that the 2V to the blower and the fact that this does not change with the change of the fan switch is also a problem. Or is this normal and I am just missing something?

The ground might be a problem but that is easily fixed if it is.

Before I run out and buy a new blower, I want to make sure the rest of it is OK. So I am very interested to hear if the voltage to the blower is correct.

Best regards,

/Soren

[bothwell_buyer]

Not sure - I'll look.

I got confused when replacing the headlights.....and found that the ground is actually switched and not the 12v feed !!

So try 12v onto the blower, and attaching a separate ground.... just in case. Seems the Japs did things differently back then!

[anchorman]

The fan motor could well be the brushes - I've done loads of them. I usually buy a set of starter brushes and then cut a set out to the same size. File the existing ones flat and then push the new pieces into the holder and hold them in with fuse wire. Put the motor back together enough that the brushes are just on the comutator and then withdraw the fuse wire - job done.

Try the motor with 12V again then play with the feed to sort it out if necessary.