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J2B



Member Since: 03 Jul 2020
Location: kent
Posts: 48

England 2010 Range Rover Vogue TDV8 Ipanema Sand

Just going to tackle this at the weekend as mine has just started to play up, glad i looked on here for pointers, Landrover wanted £121.52, got the self same genuine part at Island 4x4 £95.99 inc vat and delivery, hope i don't swear to much while doing it Laughing Laughing
Edited, completed within 30 minutes. Thumbs Up


Last edited by J2B on 20th Mar 2021 6:43pm. Edited 1 time in total

Post #588083 19th Mar 2021 10:14pm
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Merchy



Member Since: 14 Feb 2021
Location: North Wales
Posts: 1141

United Kingdom 2006 Range Rover Vogue Td6 Zermatt Silver

Quick question to those with more experience of FFRR's than me ( 3 years, years with my first one ) at 94000 miles on the car, I have had very little in the way of electrical gremlins. Am I lucky?

Would those with more experience recommend changing this BEFORE it fails, ( Due to mileage and age - 15 years old ) reading about how many fail, I am tempted to buy one and keep it as a spare in the garage just in case.
Not very expensive, and not a major job to change.

Having written the above, I know what will bloody fail tomorrow. Thank you gents.

Post #588094 20th Mar 2021 12:16am
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bgennette



Member Since: 13 Jan 2013
Location: Newcastle
Posts: 73

Australia 2003 Range Rover HSE Td6 Java Black
Useful Information when changing the FSR

A couple of things that not one of the many videos or how-tos bothered to tell us -

The FSR cooling pins face transverse, across the car, from right to left (when facing forward), so
the FSR comes out by pulling towards the right hand side.

So the panel on the right side of the centre console has to come out
1 x torqs 20 at front, 2 x transverse press clips at rear

The 'finisher' panel beneath the dash does have to be removed in order to get your hand in.
4 x torqs 20. If right hand drive may also have a large 3 blade twist plug; use a 6mm flat screw driver to undo



The mounting aperture is in the large, near vertical heating duct that is almost touching the engine compartment wall, so
the FSR's power plug is ~40mm from the wall and ~50mm above the angled heating duct

Click image to enlarge


If the FSR releases easily the ducting across the top of the footwell does NOT need to be removed, just pulled aside, if ...

The 'release' tabs for the power plug stiffen up over 10-12 years, so
you may need a 'U' shaped wire probe to release them from their clip ends in conjunction with squeezing in the tab tops front and rear

The hold-in claw on the FSR is at the top, very close to the engine wall when it is clipped into the duct, so
applying a clockwise twist while pulling out will help to release it. A wide, flat screw driver may need to be applied into the power socket to give the twist to persuade the FSR out of its aperture

The stiff tabs also make refitting difficult, so
fitting the plug to the new FSR and forcing the FSR into the aperture may require a 200mm long drift and a rubber hammer

Now that I know exactly where it is located and how to change it I estimate that the job would only take ~20 minutes from gathering the tools to washing your hands at the end.

So the real, complete tool list is -
Soft mat (for kneeling on the ground next to the car)
Torch
Torqs 20
6mm wide flat screw driver, and maybe a wider blade too
'U' shaped wire probe
200mm long drift
rubber hammer 2003 TD6, EGR delete, vortex crankcase breather update, performance chip, UHF 2 way, Android head unit, crash camera on dash, always-on rear view camera to mirror screen, LED DRL`s, Electric trailer brake controller. FSR replaced. Pulling 3T caravan all about Australia

Last edited by bgennette on 24th Oct 2021 4:16am. Edited 2 times in total

Post #609768 20th Oct 2021 7:36am
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bgennette



Member Since: 13 Jan 2013
Location: Newcastle
Posts: 73

Australia 2003 Range Rover HSE Td6 Java Black
What exactly is an FSR ???

While I'm here I thought I'd explain what this 'Resister' thing actually is.

In the early days of auto electrics, stepped fan control was via a series-string of big power resistors built into an almost complete circle. +V power came in at one end and a rotating contact selected the voltage available at any of the junctions between the resistors. If the contact went to before the first resistor the the full voltage went to the fan, if contacted after the first resistor some voltage is turned into waste heat by the resistor and a lower voltage goes to the fan. Turning the contactor further along the series created more waste heat and lower voltages = lower speeds. Turned past the end of the resistors no voltage is connected = Off. Because they got very, very hot, often the resistors were placed in the engine compartment and operated by an extension shaft from the dashboard.

In the 1980s the big resistors were replaced by much smaller ones to produce low power voltage steps (0, 2-->8V) that were then applied to an electronic throttling device to feed higher power to the fan. Electronic throttling devices are called Transistors. Bi Polar Transistors can switch quite high voltages, but their control input must be between 0 and 0.7V so a small integrated circuit translator is needed between the control resistors and the power transistor. These Power Transistors also get hot as they reduce the voltage, but not as hot as the older power resistors, AND all the heat is produced in a single, small, fixed location. To transfer the waste heat away from the Transistor into the air a large metal plate with lots of pins (to provide a large surface area) is clamped onto the transistor body. This is what the BMW 1990s to 2010s FSR is. The control knob works the first stage resistor, the translating IC is intermediate and the Power Transistor is the actual, Final Stage Resistor.

Much more efficient Field Effect Transistors that can handle large amounts of power became available in the late 1990s. And along with their introduction a new method for speed control became popular - deliver small (micro second), full power pulses to the fan motor and allow it to coast between pulses. Shorter pauses = faster speeds. The mass of the motor and fan blades will smooth out the speed and the transistor always switches from full Off to full On, therefore greatly reducing waste heat. This is what BMW uses now.

The original 'hedgehog' FSR has a voltage converter IC (Elmos 10901D) with simple over heat monitoring, an over current detector that shunts the voltage control signal to ground (thus turning off the fan and signaling the controller) and power transistors mounted underneath the circuit board (3 pins in red circles) under the black resin. Over time the heat cycling breaks the solder joints with the sensors and transistor control pins, etc leading to full-on continuous running or total failure. Its heatsink has just a few, long, large heat exchanging pins.



There have been a few versions of the circuitry over the years, from BMW and others.

The currently available, upgraded version includes a microcontroller to better manage the system, including shutting down if the transistor starts to overheat. The transistor is flat mounted through a hole in the top of the circuit board with an all copper connection to the heatsink which on this model has lots and lots of smaller pins to provide ~2 times the heat exchange surface area. This 'improvement' has just one small problem, the microcontroller is mounted close to the heatsink and so it gets hot ... and fails in all sorts of 'interesting' ways.





Around 2014 an American company produced a hybrid FSR (APSX WB FSU). Its microcontroller accepted voltage step input and sent pulse/coast signals to a pair of FETs which required no heat sink pins. Failure of these is rare. These are no longer available Crying or Very sad With todays cheap electronics I think a similar DIY solution is viable. But I don't have enough information about the type of voltage signal used (bi-directional) nor the power rating for operating the fan ... can anyone supply this? Does anyone have one of the hybrids to experiment with ?? Or maybe someone from APSX can make the details public ???

Because European vehicles operate with (to them at least are) extremes of temperature (cold winters and hot summers), vehicle fans are usually run at moderate to fast speeds with very little waste heat generated in the FSR. So not a problem for BMW. Except not all BMWs operate in that climate, for instance in Australia, after reaching a comfortable temperature, we mostly have the fans just moving the heated or cooled air slowly through the system so the FSR runs very hot, and doesn't last so long. I'm sure vehicles in the southern US have a similar profile.

There are many 'interesting' failure modes for the FSR with always On being the most common. Many of the controllers in a BMW monitor the operation of other controllers and Fan ON while engine is Off can result in wierd results. In my case the cabin air sampler fan never stopped, the indicator flashes at lock and unlock didn't happen, air suspension often had to be reset and the battery got flattened randomly.

And now you know.

bye 2003 TD6, EGR delete, vortex crankcase breather update, performance chip, UHF 2 way, Android head unit, crash camera on dash, always-on rear view camera to mirror screen, LED DRL`s, Electric trailer brake controller. FSR replaced. Pulling 3T caravan all about Australia

Post #610115 22nd Oct 2021 11:56pm
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Mullaca



Member Since: 28 Apr 2015
Location: Manchester
Posts: 4

England 2009 Range Rover Westminster TDV8 Stornoway Grey
Update re 2009 Westminster TDV8

Just replaced my FSR due to total lack of climate fan and therefore a/c or heating. Many thanks to all contributors on here, other forums and various YouTubers, I bought a Chinese copy off Amazon UK for £21.99 and fitted it relatively painlessly using all the advice I'd read.

One point of note is that on my RHD car, the foot-well heating duct is held in place by 2 torx screws which
I haven't seen mentioned anywhere else. getting these out was by far the most frustrating part of the job, having to maneuver the torx driver into the spaces above the pedals and behind the fascia panel below the steering wheel. Once those screws were removed, the duct simply drops out of the way without any complex manipulation as mentioned elsewhere.

Immediately I plugged the new FSR in I tested and my climate control was fully restored.

Clearly now need to hope that a faulty fan is not the cause of the FSR failure as described elsewhere, as I don't look forward to cutting holes behind the dash facia to replace the fan.

Post #669792 25th Jul 2023 3:33pm
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