Marc Shaw

Hi,

Looking for the part number for the temp sensor that connects to the rear blower in the left of the engine compartment (in a LHD). My blower runs high speed all the time, I've swapped relays with no joy so I think the sensor is mucked up...I'd like to replace it but can't find the part number for it.

See photo below.

Thanks.....Marc

gfunk

964 659 120 00 Outer sensor (Part #12 in attached diagram)

Greg

Karl 964C4

Marc,

Check the resistor (part#10) first.

It is this part that is used to have the two speeds for the ventilator,

Regards,
Karl

JasonAndreas

964-616-550-02 is the heater blower resistor but before you replace it try resetting it first (if you have one that is resettable).

DaveK

If he doesn't comment on this thread, you could try PM'ing Kevin (Warmfuzzies). I'm sure he had exactly this problem just before Christmas last year. I know he did find the problem in the end - and there was a thread on it (but can't remember if it included the final solution). Try a search for posts by him around mid-December.

JasonAndreas

For fault code 44:

1. Check voltage on terminals 30 and 30C.
2. Check whether motor is seized mechanically, e.g. bridge terminals 30 and 87.
3. Check electric leads from relay term. 87 to motor for breaks and ground short.
4. Check electric leads from motor to heater/air conditioner regulator G19 for breaks.

warmfuzzies

Morning.

Pt no:12 was a problem, so replaced, this if disconnected makes the fan run fill tilt.......that was done before my original post
I also replaced the resistor as this was intermittant.
Check resistances as jason has identified above, these will tell you if the wiring has a high resistance path. (most important)
You can also bridge the terminals as in my original post here:-
https://rennlist.com/forums/showthre...ghlight=blower

I replied with an answer ;-)))

kevin

warmfuzzies

The resistor is only .3ohms, very small. That's one of the things that threw me in the first place, add in a couple of other bad joints and the motor will simply not run in slow speed, that's my experience.

I checked the wiring with the resistor in place, and then from each connector on the resistor to the relay holder itself, trying to negate as much as possible.

You might also want to check resistance on the motor itself, I have read that some people have found the internal connections have come adrift, though I've no experience of this myself.

My hammer codes were open circuit, it quite clearly wasn't open circuit, but if a resistance of "X" is expected and its a bit higher, then I guess open circuit, could be valid as a code....

Did you jumper the relay pins? as suggested in my previous thread? That way you will establish if the power can reach the motor and run it ok.

If you go down the route of removing the CCU as I did then take care and disconnect the battery first, before attempting removal, and make sure the car has not been run for a while as the small fan on the back of the CCU could still be live/running......Pop the buttons/sliders first, use four small drills/ proper radio removal tools push in and remove CCU, then unclip the front of the unit, Yoiu have to do this otherwise it hits the indicator stalk.
I then disassembled mine and cleaned all contacts, the small fan, oild the bearings and blew all teh dust/crap out of the sensor unit.......then reassembled it, took about 1 hour.

kevin

Marc Shaw

Finally got my multimeter back and got some time to scrounge in the back engine bay.

So here's what I know:

1. Voltage at 30C is 12.2 V
2. Voltage at 30 is 12.1 V
3. Resistance across resistor is 2 ohm
4. Resistance across motor is 1 ohm
5. Jumpering 30 and 87C runs motor at high speed
6. Jumpering 30C and 87C runs motor at low speed
7. Shorted across part #12 and still runs at high speed
8. Resistances from terminal 87 across resistor is 1 ohm
9. Resistances from terminal 87C across resistor is 1.2 ohm
10. Resistance from all other terminals (30, 30C, 85, 86, 86C) across resistor are all open circuit.
11. I can't find any breaks or shorts to ground on wires from 87 to motor

I don't know what or where regulator G19 is.

Any other ideas?

Many thanks....Marc

warmfuzzies

What condition does the resistor look in? It sounds as though the circuitry is working ok if you can get the motor to run at slow speed.....I know you replaced it but it may not be A ok, 2ohms is too much.
Shorting pt 12 will get you a high speed fan, it's used to tell the system that the engine needs some cooling.
I checked pt 12 on mine with a hair dryer, connected, just out of the hose, gently warm it up. Adrains book references some temps/resistance to measure at the DME on page 390. I just played about with mine warming and cooling it to make sure the fan would come on and off.
Do you still have the old reisitor? if so butcher it, snip of the connections so you are left with just the resistive coil, make up or just plain push on your wiring to the coil.
Now please bear in mind this coil gets hot, very hot........so play safe here. then if you can place the coil on something that will not burn or cause damage with the wiring attached to the coil see what happens when you ask for heat, above 21 IIRC should get the fan to cycle in slow mode continuously.
That's the extent of my knowledge I'm afraid.....Just be carefull playing with the resistor, it gets really hot.

kevin