My 2002 Disco AC or heater fan only works on high and my best research says its the blower motor resistor. I have pulled it from the vehicle and would like to test it. Does someone on here have one they can get the Ohm reading from pin 2-4, 3-4 and 1-2? Maybe someone knows a procedure on here that I couldn't find? Then tell me which is which?

Next I called Autozone and they want $273 for this stupid little part and again best research says I can replace the resistor if I know how but having a hard time finding the resistor. I also called salvage yard and they want $60 for this part. I think the resistor is 2SD1460 and is around $5. Now I feel this is a much better way then spending $273 for this at AutoZone or even $60 for this stupid little part. Im sure someone has had the same thought on this? Surely Im not the only one that's willing to fork over even a fraction of that price when the part that has fail is only $5. Help someone!!

 

According to parts manual the part is number JNH100000.

2002 Land Rover Discovery. #JNH100000: HVAC Blower Motor Resistor. RESISTOR.

 

Good lead Joe, this price looks more favorable:

JNH100000 | Resistor - Land Rover Part JNH100000

 

There has got to be a write up somewhere of how to replace the resistor without having to buy the whole thing. It seems like a simple solder job!!!

 

I have a 2000 D2 and the heat/ac blower will not blow air cold or hot. I checked fuses inside the cab and under the hood anything with a fan symbol got checked. The indicator lights all come on but no forced air coming from vents or dash. Coolant level in reservoir is good. Any help would be much appreciated, you guys have helped me on many different occasions and I cant thank you enough.


Thanks again

 

Part JGH10002(Rover) and part 79330ST3E01 (Honda Civic 95-00) appears to be very similar. The plate is different, but the plug and mounting screw holes look to be the same. I think it could be trimmed to work. It is $13 and change on Amazon and cheaper on the auction sites. Repair kits available for about $6 that should solder right into our boards. NOTE: I am ASSUMING compatibility.

Per one UK dyi website the above wire coil resistor impedances are 1. 2.1 ohms 2. 1.5 ohms 3. 1.0 ohms

The wire coils cool in the air flow of the fan. Homemade wire coils: 28 gauge bare Constantan wire(.015 in /.375 mm)
in three lengths, 50 cm (abt 2 inches), 35 cm (abt 1 3/8 inches), 23 cm (abt 7/8 inch), coil each wire tightly around a very small shaft perhaps a toothpick or ink pen refill(a pen or pencil may be too big?), spread coil a little so air flow will cool, ready to solder.

 

More info about the wire coil resistors on the JGH10002(NOT original to the Discovery, but other Rovers). Note: there are different impendances mentioned for the JGM100050 part(Below article). This indicates a different gauge wire in the original part. Both part numbers seem to fit same model Rovers?


A common fault on the MG-Rover 200/400/MGF/25/45/ZR/ZS models is failure of the heater fan speeds, usually on positions 1 and 2.

The speed control is achieved by using different value resistors switched in series with the motor, a three resistor pack is mounted in the fan housing behind the glovebox. Position 4 bypasses the resistor pack and allows the fan to run at full speed, this is a useful test as it proves that the Fuse, Relay and Fan Motor are working fine

The original pack used a special resistance wire called Constantan wound into small coils to make up the individual resistors, a combination of metal fatigue caused by heat and vehicle vibration and the wire being too thin results in the coils breaking.

A genuine replacement resistor pack (original part number: JGM100050) will cost £30 and upwards, however the part still has the inherent weaknesses mentioned above and will fail again in time.

A simple solution to repair the failed pack is to replace the coiled resistors with high power ceramic resistors. The original MG-R values were 0.27 ohms, 0.75 ohms and 1.48 ohms.

Because the resistors reduce the voltage to the fan (thus reducing it's speed) the "wasted" voltage is converted to heat - the resitors get hot in the process!

Therefore the resistors have to have a minimum "Wattage" rating to enable them to pass the current without failing and still be able to operate within their design ratings, the minimum wattage should be 11 watts. Anything lower will burn out quite quickly! It is feasible to use larger wattage resistors ie. 25 watts, but their use will be limited due to their larger physical size.

Try to avoid using the same value resistor in all three positions, ie. 3 x 1.5 ohm resistors, as the speed on position 1 (and possibly 2) will be too low. It is also tempting to use this value as it is readily available in an 11 watt resistor, but due to the value of current flowing in the fan circuit it will exceed the 11 watt rating.

If you cannot find values close to the original mentioned above it is quite acceptable to use two resistors in parallel to achive one of the desired values, as an example...

We need an 0.27 ohm 11 watt (or higher) resistor, if you connect two 0.47 ohm 7 watt resistors in parallel you have a 0.23 ohm 14 watt resistor - extremely close to the original.

Similar combinations can be used for the other resistors. Remember when you connect resistors of equal value in parallel the total resistance halves, but the power disippation (wattage) doubles.

I hope this has been somewhat informative!

Technozen_electronics

 

@ Coldmieser

If you have no fan speed at maximum speed then your resistors pack are likely fine. The pack does not affect maximum speed. Maximum speed is direct 12v power. If this is the case then your problem is likely the interior fuse box/block at fuses 6 and 7 (A/C and rear A/C, if equipped blowers). A poor connection from rear connector to front fuse. Perhaps broken solder, will read 12v but fail under load. Other fuses are fine, just those two. New fuse block or bypass with individual inline fuses.