Aspirator fan fix

[drew]

It appears that the 2002-2005/6 CR-V has a [near] exact aspirator fan as the NSX.

If you run the basic DENSO 173000 part number on the back through a search engine you will find that other manufacturers (including Range Rover, Jaguar, Porsche) use a slighly different configuration unit that can be robbed for parts.

 

[SWFL_NSX]

It appears that the 2002-2005/6 CR-V has a [near] exact aspirator fan as the NSX.

If you run the basic DENSO 173000 part number on the back through a search engine you will find that other manufacturers (including Range Rover, Jaguar, Porsche) use a slighly different configuration unit that can be robbed for parts.

Nice sleuthing! Adjusting the nut on the back of mine worked, but this is goods news.

 

[SWFL_NSX]

My fan has started to make noise again so I looked around for the Denso part number. Here is a link to a porsche forum describing all the different vehicles that the 173000 fan was used on.

https://rennlist.com/forums/964-forum/710247-where-to-get-new-ccu-denso-rear-fan-2.html

Oddly, it looks like the fan was only used on CRVs in Europe. The Honda part number is 80530-SCA-G21 and you can order it from the UK via this link. https://www.parts-honda.uk/honda-ca...-CONDITIONER-SENSOR-/17SKN501/B__6100/6/20217

I'm going to try to order it this afternoon. When it arrives I'll try to do some testing on the fan itself and the sensor to verify the output is the same.

It might be possible to find this part state-side by finding the actual part numbers for the other manufacturers.

 

[Old Guy]

The fan looks like it may work. Do check out the RTD to make sure that it has the calibration curve as the RTD in the NSX. Otherwise, you may generate an error code on the CCU or have some temperature control issues.

The correct NSX part is 80530-SL0-A01. The base part # is the same as for the CRV. The cost for the CRV sensor is about 1/3 the cost of the NSX part, even from Amayama. If the CRV sensor works that would be a nice part substitution.

 

[ZX4NSX]

Any updates on an alternative fan that works with no issues?

 

[SWFL_NSX]

Just ordered the CRV version via Amayma-30$ plus 20$ shipping. Should get here first week in December.

I'd like to test the fan component and the sensor component separately to see if the whole thing is plug and play, or if the new fan has to be swapped onto the old sensor.

Can anybody sketch out a set of tests I can perform to see if the sensor is the same? I have a couple of DMMs, a oscilloscope, a soldering iron, but very little knowledge of electronics!

 

[MotorMouth93]

Measure resistance across a range of temperatures. Put both parts in the fridge for a while then check the resistance. Put them in an oven at 150 or 200f and check. Let them both sit somewhere in the house and check.

 

[Honcho]

Just ordered the CRV version via Amayma-30$ plus 20$ shipping. Should get here first week in December.

I'd like to test the fan component and the sensor component separately to see if the whole thing is plug and play, or if the new fan has to be swapped onto the old sensor.

Can anybody sketch out a set of tests I can perform to see if the sensor is the same? I have a couple of DMMs, a oscilloscope, a soldering iron, but very little knowledge of electronics!

I'm really interested in your update. I have to clean my ancient one and if I can just buy a replacement for $30, I'm in!

 

[Old Guy]

I'd like to test the fan component and the sensor component separately to see if the whole thing is plug and play, or if the new fan has to be swapped onto the old sensor.

Can anybody sketch out a set of tests I can perform to see if the sensor is the same? I have a couple of DMMs, a oscilloscope, a soldering iron, but very little knowledge of electronics!

A bit late to the party; but, if you look at page 22-87 of the 1991 service manual, it provides you with a graph of the resistance versus temperature for the actual sensor along with the terminal numbers for the measurement. If you have a separate calibrated temperature measurement probe (or good thermometer) to give you the actual temperature I would suggest resistance measurements at about 120 F (oven test), room temperature and around 40F (or whatever your refrigerator is operating at).

Assuming that the module physically fits, to do a straight plug and play part swap you will need to confirm that the plug and pin out arrangement for the CRV sensor is the same for the NSX sensor. If the pin arrangement is different you may be able to just de pin and re arrange. If the plug shell is different you may be able to just de pin and swap shells if the actual metal terminals are the same. If not, you will have to do a cut and splice.

 

[SWFL_NSX]

Thanks everyone. The CRV aspirator came today and it's definitely the same physical fit and has the same connector and pin outs. Unfortunately the thermistor is a very different spec than the one in our NSX. At 68*F my NSX aspirator measured 6.38kΩ and the CRV version measured 2.6k[FONT=-apple-system, BlinkMacSystemFont, Segoe UI, Liberation Sans, sans-serif]Ω. [/FONT]

[FONT=-apple-system, BlinkMacSystemFont, Segoe UI, Liberation Sans, sans-serif]Next step is to swap the CRV motor onto the NSX thermistor body. Before I do that, does anybody know a way to measure the RPM of the fan? I thought there was a way with the oscilloscope but my google-fu is lacking. I only have two leads-do I just hook up the scope and adjust till I get a clear picture?

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[Old Guy]

My gut reaction is same Denso part number, same nominal RPM.

That said, depending on what type of motor it is, you may be able to estimate the RPM by monitoring the motor current with an oscilloscope. Modern small fans (like cooling fans in computers) are commutator less, permanent magnet rotor motors which use a Hall sensor device to sense the polarity of the PMG field and switch the current in the static armature to create a rotating magnetic field which drags along the permanent magnet rotor. As the Hall device switches the current to the winding you should be able to see those current fluctuations with an oscilloscope. You would need a resistive shunt in the current supply which turns the motor current into a small voltage that the scope can read, or fork over the dollars for a high frequency Hall probe which can measure the DC current directly and generate an output for the scope. If you know the number of motor poles, you measure the time between current switching events and you can estimate the RPM. This presumes that the motor is a Hall switched device. Given the late 1980s design vintage of the first NSX, I am thinking that predates the Hall switching devices and that this might be some kind brushed printed pancake motor. Those motors are generally ripple less and I don't think you can suss out the RPM by monitoring the motor current.

On the odd chance that this is a Hall device switched motor you would have to pull it apart to determine the number of poles which is something I personally would not do. I would just be inclined to put your new motor and fan in the original housing with its thermistor and be done with it.

 

[SWFL_NSX]

My gut reaction is same Denso part number, same nominal RPM.

Sounds reasonable to me-thanks.

I removed the thermistor from each aspirator unit, de-pinned both thermistors from their plugs and swapped the NSX thermistor onto the CRV fan body. If you do it right you don't have to cut the factory heat shielding, but will have to make a small cut in the foam on each side of the plugs to de-pin the wires. From the NSX aspirator, re-use the plastic piece that holds the thermistor to the rest of the aspirator body; it has a special tape that prevents squeeking between the aspirator assembly and the center console.

After re-assembly I did a brief test on the NSX but won't be doing a road test until I re-install the radio. If anything goes wrong with my CCU I'll update this thread, but for now this seems like an easy way to save $100

 

[1M3ANM3]

Sounds reasonable to me-thanks.

I removed the thermistor from each aspirator unit, de-pinned both thermistors from their plugs and swapped the NSX thermistor onto the CRV fan body. If you do it right you don't have to cut the factory heat shielding, but will have to make a small cut in the foam on each side of the plugs to de-pin the wires. From the NSX aspirator, re-use the plastic piece that holds the thermistor to the rest of the aspirator body; it has a special tape that prevents squeeking between the aspirator assembly and the center console.

After re-assembly I did a brief test on the NSX but won't be doing a road test until I re-install the radio. If anything goes wrong with my CCU I'll update this thread, but for now this seems like an easy way to save $100

what was the final verdict ?

 

[SWFL_NSX]

what was the final verdict ?

Works fine! You can bench test the Thermistor while it's out of the car to be sure it's within spec, but I don't think they go bad very often.